American Mathematics Competitions
GRAND STATISTICS
2011 AMC 10 A Results
TOTAL NUMBER of official students taking exam: 70919
Number of unofficial participants: 483
Average score of participants: 67.7
Average score for female students is: 62.2 ( 25692 Students)
Average score for male students is: 73.0 ( 32739 Students)
Average score for unspecified gender is 65.1 ( 12488 Students)
Average score for grade 10 is: 70.5 ( 35727 Students)
Average score for grade 9 is: 62.4 ( 24410 Students)
Average score for grade 8 and below is: 81.3 ( 5018 Students)
Average score with unknown grade: 60.8 ( 5764 Students)
AIME qualifying score = 117.0 or better
Number of AIME qualifers 3128
Number of schools returning results 2451
Average school winning score 101.88
American Mathematics Competitions
GRAND STATISTICS
2011 AMC 12 A Results
TOTAL NUMBER of official students taking exam: 74665
Number of unofficial participants: 472
Average score of participants: 66.8
Average score for female students is: 62.5 ( 26418 Students)
Average score for male students is: 70.0 ( 37477 Students)
Average score for unspecified gender is 66.2 ( 10770 Students)
Average score for grade 13 is: 67.9 ( 66 Students)
Average score for grade 12 is: 67.7 ( 29957 Students)
Average score for grade 11 is: 66.3 ( 34889 Students)
Average score for grade 10 is: 68.3 ( 4469 Students)
Average score for grade 9 is: 65.7 ( 1348 Students)
Average score for grade 8 and below is: 73.8 ( 214 Students)
Average score with unknown grade: 62.8 ( 3722 Students)
AIME qualifying score = 93.0 or better
Number of AIME qualifers 4768
Number of schools returning results 2622
Average school winning score 92.32
Average school team score 250.95
American Mathematics Competitions
GRAND STATISTICS
2011 AMC 10 B Results
TOTAL NUMBER of official students taking exam: 33723
Number of unofficial participants: 371
Average score of participants: 72.2
Average score for female students is: 66.7 ( 12088 Students)
Average score for male students is: 75.9 ( 15097 Students)
Average score for unspecified gender is 73.8 ( 6538 Students)
Average score for grade 10 is: 73.9 ( 16661 Students)
Average score for grade 9 is: 66.6 ( 10249 Students)
Average score for grade 8 and below is: 78.7 ( 3477 Students)
Average score with unknown grade: 74.2 ( 3336 Students)
AIME qualifying score = 117.0 or better
Number of AIME qualifers 2038
Number of schools returning results 1263
Average school winning score 100.13
American Mathematics Competitions
GRAND STATISTICS
2011 AMC 12 B Results
TOTAL NUMBER of official students taking exam: 30846
Number of unofficial participants: 221
Average score of participants: 64.9
Average score for female students is: 58.7 ( 9987 Students)
Average score for male students is: 68.3 ( 15095 Students)
Average score for unspecified gender is 67.0 ( 5764 Students)
Average score for grade 13 is: 70.5 ( 86 Students)
Average score for grade 12 is: 63.7 ( 9959 Students)
Average score for grade 11 is: 63.9 ( 14251 Students)
Average score for grade 10 is: 69.7 ( 2429 Students)
Average score for grade 9 is: 69.7 ( 903 Students)
Average score for grade 8 and below is: 75.9 ( 326 Students)
Average score with unknown grade: 67.6 ( 2892 Students)
AIME qualifying score = 97.5 or better
Number of AIME qualifers 2383
Number of schools returning results 1447
Average school winning score 91.60
Average school team score 238.72
2011 AMC Contest Score Distributions
-----------------------------------------------
score 12A 12B 10A 10B
-----------------------------------------------
150.0 4 5 16 26
148.5
147.0
145.5 1 9 24 5
144.0 7 10 29 60
142.5
141.0 1 3 50 7
139.5 10 29 32
138.0 6 9 46 93
136.5 9 13 57 10
135.0 6 19 81 46
133.5 1 5 33 45
132.0 16 33 182 173
130.5 12 13 97 63
129.0 9 17 104 82
127.5 31 15 159 104
126.0 38 50 355 240
124.5 15 20 172 101
123.0 43 40 246 115
121.5 71 46 323 158
120.0 65 50 483 344
118.5 72 53 242 131
117.0 72 64 400 203
115.5 46 62 332 246
114.0 127 113 636 514
112.5 98 71 419 199
111.0 91 84 460 241
109.5 148 107 454 274
108.0 211 151 732 569
106.5 115 142 454 226
105.0 195 155 551 293
103.5 222 141 577 341
102.0 314 242 781 633
100.5 345 215 540 276
99.0 370 218 654 362
97.5 307 197 660 353
96.0 588 287 920 640
94.5 645 351 699 350
93.0 464 277 728 372
91.5 578 342 713 431
90.0 909 446 1027 690
88.5 870 450 745 367
87.0 937 390 819 436
85.5 1014 399 891 529
84.0 1384 520 1155 796
82.5 1444 518 932 437
81.0 1534 529 1000 482
79.5 1563 455 1092 557
78.0 2047 678 1329 767
76.5 2167 639 1072 548
75.0 2108 607 1189 567
73.5 2306 600 1256 587
72.0 3091 818 1609 893
70.5 2769 716 1252 593
69.0 2767 729 1384 591
67.5 3012 780 1546 659
66.0 3620 1003 1969 921
64.5 3039 804 1539 661
63.0 3013 809 1641 650
61.5 2781 854 1725 706
60.0 3368 1087 2108 1020
58.5 2527 847 1808 687
57.0 2274 873 1778 730
55.5 2201 907 1798 739
54.0 2743 1095 2192 917
52.5 1862 827 1779 654
51.0 1627 806 1772 694
49.5 1561 789 1730 653
48.0 1829 985 2157 864
46.5 1088 760 1514 596
45.0 986 704 1577 547
43.5 847 659 1417 547
42.0 1047 811 1804 721
40.5 539 485 1150 380
39.0 435 421 1068 396
37.5 439 416 1009 380
36.0 526 531 1248 519
34.5 185 243 659 233
33.0 156 209 568 225
31.5 148 170 547 206
30.0 248 292 753 328
28.5 53 101 332 130
27.0 24 68 257 121
25.5 47 65 234 69
24.0 101 119 415 199
22.5 10 33 114 63
21.0 12 23 102 54
19.5 9 27 79 43
18.0 31 49 159 98
16.5 1 11 24 15
15.0 10 23 15
13.5 3 7 21 13
12.0 11 16 65 49
10.5 3 10 3
9.0 2 8 3
7.5 5 6 3
6.0 2 5 17 11
4.5 2 1
3.0 1
1.5
4 1 5 1
American Mathematics Competitions
SCORE DISTRIBUTION
2011 AMC 10 A Results
GENDER and GRADES
score ----gender----------- -----------------grade-----------------
male female ? <=6 7 8 9 10 ?
--------------------------- ---------------------------------------
150.0 15 1 1 2 2 5 5 1
148.5
147.0
145.5 19 3 2 2 2 8 11 1
144.0 21 2 6 1 5 5 16 2
142.5
141.0 36 12 2 16 14 19 1
139.5 23 5 1 1 5 8 14 1
138.0 36 4 6 1 8 10 24 3
136.5 39 10 8 1 2 12 12 26 4
135.0 61 11 9 2 7 12 17 40 3
133.5 23 5 5 1 2 6 9 13 2
132.0 144 23 15 3 11 31 46 85 6
130.5 70 18 9 2 4 23 18 48 2
129.0 79 13 12 1 5 11 33 51 3
127.5 116 30 13 10 13 32 99 5
126.0 265 60 30 3 20 38 86 204 4
124.5 121 32 19 2 7 28 35 95 5
123.0 159 65 22 2 10 32 43 152 7
121.5 211 73 39 4 14 38 60 194 13
120.0 347 94 42 4 21 60 95 292 11
118.5 160 58 24 3 8 17 50 160 4
117.0 254 109 37 5 15 38 75 258 9
115.5 220 85 27 4 14 35 71 199 9
114.0 434 142 60 6 24 81 96 416 13
112.5 245 123 51 5 13 32 94 258 17
111.0 274 134 52 3 18 45 109 275 10
109.5 280 123 51 3 8 37 71 314 21
108.0 458 189 85 5 27 61 142 468 29
106.5 265 134 55 6 17 44 84 289 14
105.0 335 148 68 5 19 54 127 317 29
103.5 319 160 98 4 17 46 119 359 32
102.0 459 215 107 6 21 63 162 499 30
100.5 288 171 81 5 19 53 130 298 35
99.0 383 153 118 7 23 54 139 387 44
97.5 374 183 103 9 18 50 146 407 30
96.0 527 254 139 5 28 60 206 583 38
94.5 369 210 120 11 23 52 167 405 41
93.0 387 226 115 10 23 50 187 425 33
91.5 390 198 125 6 19 51 194 389 54
90.0 557 325 145 15 22 74 229 627 60
88.5 395 224 126 12 17 49 194 421 52
87.0 426 263 130 12 26 63 226 438 54
85.5 454 261 176 10 31 52 244 480 74
84.0 650 294 211 16 33 65 320 627 94
82.5 485 258 189 10 17 46 285 502 72
81.0 507 285 208 11 24 51 297 539 78
79.5 572 318 202 11 20 59 338 592 72
78.0 704 394 231 9 25 72 418 712 93
76.5 530 332 210 11 16 45 346 583 71
75.0 604 374 211 10 22 65 385 617 90
73.5 640 367 249 10 25 44 415 640 122
72.0 840 473 296 13 30 74 531 835 126
70.5 625 413 214 14 18 48 444 633 95
69.0 651 470 263 11 22 44 488 695 124
67.5 742 484 320 20 21 61 537 783 124
66.0 941 642 386 19 25 79 712 977 157
64.5 725 502 312 16 13 60 584 745 121
63.0 698 628 315 9 16 50 613 803 150
61.5 742 629 354 15 15 51 659 807 178
60.0 990 737 381 18 22 72 786 1037 173
58.5 723 734 351 10 25 51 717 840 165
57.0 701 706 371 13 16 52 691 832 174
55.5 732 719 347 19 18 47 743 815 156
54.0 950 815 427 18 18 70 867 1012 207
52.5 693 762 324 13 14 46 754 806 146
51.0 662 757 353 19 12 48 708 826 159
49.5 642 766 322 13 14 33 710 782 178
48.0 848 935 374 16 21 53 894 958 215
46.5 561 676 277 8 10 40 638 669 149
45.0 538 737 302 5 14 33 679 690 156
43.5 490 675 252 10 9 26 621 599 152
42.0 654 836 314 9 10 37 723 837 188
40.5 413 540 197 12 3 21 514 480 120
39.0 371 521 176 5 5 31 461 468 98
37.5 307 496 206 7 5 18 430 432 117
36.0 440 588 220 8 7 36 527 559 111
34.5 198 345 116 3 4 16 266 300 70
33.0 162 311 95 4 4 15 227 262 56
31.5 162 280 105 6 4 11 232 240 54
30.0 234 374 145 6 2 17 299 330 99
28.5 96 171 65 3 2 7 130 155 35
27.0 70 137 50 3 4 4 117 103 26
25.5 64 131 39 6 1 2 102 97 26
24.0 147 197 71 5 11 167 174 58
22.5 26 65 23 2 4 31 60 17
21.0 32 52 18 1 3 35 44 19
19.5 27 42 10 2 28 36 13
18.0 50 84 25 1 3 62 60 33
16.5 6 16 2 12 12
15.0 9 11 3 2 7 10 4
13.5 5 13 3 12 6 3
12.0 24 30 11 1 28 30 6
10.5 2 7 1 5 4 1
9.0 2 6 1 2 5
7.5 3 3 1 2 2 1
6.0 8 5 4 9 4 4
4.5 1 1 2
3.0
1.5
2 3 2 1 2
American Mathematics Competitions
SCORE DISTRIBUTION
2011 AMC 12 A Results
GENDER and GRADES
score ----gender------------ ---------------------------grade---------------------------
male female ? <=6 7 8 9 10 11 12 13 ?
---------------------------- -----------------------------------------------------------
150.0 4 2 2
148.5
147.0
145.5 1 1
144.0 6 1 1 2 3 1
142.5
141.0 1 1
139.5
138.0 5 1 1 1 3 1
136.5 8 1 1 3 5
135.0 4 2 1 2 2 1
133.5 1 1
132.0 14 2 1 2 8 4 1
130.5 9 2 1 2 2 4 4
129.0 8 1 2 5 2
127.5 23 5 3 3 1 12 14 1
126.0 31 5 2 3 4 17 14
124.5 15 1 2 1 2 4 5
123.0 37 5 1 2 5 21 15
121.5 53 11 7 2 9 38 21 1
120.0 56 6 3 1 1 2 2 15 18 26
118.5 56 9 7 1 5 9 28 26 3
117.0 54 8 10 1 2 13 27 27 2
115.5 38 4 4 1 9 14 21 1
114.0 99 22 6 1 2 4 16 52 51 1
112.5 81 9 8 2 2 10 46 36 1 1
111.0 78 9 4 1 1 1 8 44 35 1
109.5 110 28 10 3 1 16 61 64 3
108.0 154 38 19 1 4 12 95 96 3
106.5 94 12 9 3 7 52 50 2 1
105.0 147 32 16 8 14 76 94 3
103.5 158 38 26 1 1 3 23 93 98 3
102.0 242 47 25 1 9 17 153 131 3
100.5 252 50 43 2 6 26 145 156 10
99.0 275 68 27 6 24 169 164 7
97.5 213 58 36 2 8 19 152 120 6
96.0 403 114 71 3 14 37 263 250 1 20
94.5 415 133 97 1 2 5 13 64 280 258 1 21
93.0 327 99 38 1 2 9 41 217 189 5
91.5 371 138 69 3 12 37 267 245 14
90.0 588 189 132 1 1 10 52 416 394 35
88.5 603 164 103 2 1 19 67 362 389 2 28
87.0 594 228 115 2 1 2 11 59 412 417 2 31
85.5 590 269 155 2 2 16 62 452 430 1 49
84.0 876 326 182 2 4 11 71 644 600 2 50
82.5 866 375 203 5 16 90 633 632 2 66
81.0 911 412 211 2 19 82 708 669 1 53
79.5 898 419 246 1 3 17 76 689 694 3 80
78.0 1228 546 273 1 5 26 126 910 881 98
76.5 1172 649 346 1 3 37 128 958 956 2 82
75.0 1164 600 344 3 18 130 943 900 114
73.5 1243 695 368 2 1 32 131 1065 967 3 105
72.0 1714 881 496 3 46 174 1401 1323 2 142
70.5 1470 869 430 7 49 166 1245 1138 2 162
69.0 1402 901 464 1 7 29 148 1354 1096 1 131
67.5 1527 994 491 1 7 56 181 1396 1225 3 143
66.0 1852 1222 546 2 5 66 165 1733 1471 3 175
64.5 1453 1136 450 1 2 2 51 193 1429 1205 1 155
63.0 1415 1153 445 8 58 195 1380 1236 2 134
61.5 1237 1126 418 1 6 62 167 1340 1069 4 132
60.0 1664 1212 492 2 8 63 199 1587 1321 5 183
58.5 1090 1070 367 5 44 170 1198 962 3 145
57.0 954 985 335 3 47 138 1087 882 1 116
55.5 910 978 313 1 3 50 122 1033 872 2 118
54.0 1191 1168 384 2 4 64 151 1327 1052 1 142
52.5 768 851 243 1 2 36 104 935 705 2 77
51.0 589 801 237 1 1 3 43 99 794 584 3 99
49.5 593 757 211 2 5 34 80 761 586 1 92
48.0 705 865 259 1 2 43 106 890 654 1 132
46.5 366 567 155 4 21 70 522 401 2 68
45.0 327 518 141 1 26 56 512 326 1 64
43.5 295 457 95 1 18 50 441 294 43
42.0 402 508 137 1 3 22 59 523 361 2 76
40.5 176 290 73 1 14 34 264 192 34
39.0 131 247 57 8 25 220 150 32
37.5 145 233 61 2 8 23 215 148 43
36.0 177 280 69 10 22 265 185 1 43
34.5 64 103 18 1 2 5 14 91 62 10
33.0 45 97 14 1 2 1 83 57 12
31.5 44 73 31 11 68 48 21
30.0 98 105 45 1 1 5 16 103 80 42
28.5 10 29 14 3 2 17 20 11
27.0 9 11 4 1 10 9 4
25.5 14 23 10 1 2 21 13 10
24.0 38 43 20 1 4 52 35 9
22.5 4 5 1 4 6
21.0 3 8 1 7 3 2
19.5 1 8 4 4 1
18.0 12 11 8 3 11 8 9
16.5 1 1
15.0
13.5 1 2 1 1 1
12.0 4 5 2 1 7 3
10.5
9.0
7.5
6.0 1 1 1 1
4.5
3.0
1.5
4 4
American Mathematics Competitions
SCORE DISTRIBUTION
2011 AMC 10 B Results
GENDER and GRADES
score ----gender----------- -----------------grade-----------------
male female ? <=6 7 8 9 10 ?
--------------------------- ---------------------------------------
150.0 17 4 5 2 2 8 11 3
148.5
147.0
145.5 5 2 3
144.0 45 2 13 1 1 3 11 31 13
142.5
141.0 6 1 1 1 3 2
139.5 21 4 7 1 1 6 7 11 6
138.0 62 7 24 3 10 15 47 18
136.5 7 3 1 1 3 2 3
135.0 33 6 7 2 7 5 27 5
133.5 26 7 12 1 2 5 5 24 8
132.0 109 20 44 2 2 18 27 92 32
130.5 36 10 17 1 7 13 32 10
129.0 53 11 18 2 6 16 46 12
127.5 57 30 17 3 8 17 66 10
126.0 140 46 54 1 10 13 30 145 41
124.5 61 20 20 1 1 12 22 48 17
123.0 66 26 23 1 1 7 31 57 18
121.5 100 25 33 4 14 34 93 13
120.0 200 72 72 2 5 33 67 186 51
118.5 77 24 30 4 3 9 22 75 18
117.0 108 60 35 11 22 37 112 21
115.5 131 69 46 6 8 20 45 139 28
114.0 268 130 116 4 20 45 80 286 79
112.5 99 63 37 4 16 43 112 24
111.0 129 75 37 2 12 19 53 136 19
109.5 142 68 64 2 9 27 47 157 32
108.0 294 147 128 4 19 37 106 333 70
106.5 122 60 44 1 5 15 52 129 24
105.0 150 83 60 1 15 28 69 154 26
103.5 181 91 69 3 19 25 70 188 36
102.0 349 166 118 6 24 61 117 362 63
100.5 144 79 53 8 8 24 54 161 21
99.0 172 131 59 5 11 32 105 183 26
97.5 175 110 68 5 17 32 94 172 33
96.0 325 176 139 9 30 55 148 326 72
94.5 176 115 59 7 17 27 83 189 27
93.0 182 115 75 4 13 37 107 169 42
91.5 204 136 91 10 12 48 102 220 39
90.0 324 221 145 6 31 65 169 353 66
88.5 166 114 87 2 20 27 97 183 38
87.0 191 147 98 5 12 32 129 218 40
85.5 259 169 101 14 17 46 133 270 49
84.0 393 237 166 15 30 63 192 420 76
82.5 187 155 95 4 12 31 119 233 38
81.0 225 158 99 6 20 35 152 223 46
79.5 267 170 120 5 17 40 161 282 52
78.0 378 227 162 14 26 50 203 402 72
76.5 241 197 110 25 13 32 167 276 35
75.0 263 199 105 17 17 36 160 297 40
73.5 262 200 125 14 14 46 163 294 56
72.0 400 308 185 13 24 61 246 441 108
70.5 261 209 123 24 11 40 207 252 59
69.0 253 212 126 15 22 31 180 279 64
67.5 323 238 98 18 21 30 226 316 48
66.0 389 331 201 20 19 48 295 435 104
64.5 276 258 127 10 18 33 232 315 53
63.0 274 250 126 16 22 29 234 299 50
61.5 289 279 138 17 19 28 274 301 67
60.0 433 393 194 15 19 49 368 473 96
58.5 299 257 131 14 14 37 210 365 47
57.0 286 322 122 4 11 28 276 364 47
55.5 302 291 146 11 10 25 278 334 81
54.0 397 357 163 15 19 49 299 462 73
52.5 261 267 126 8 13 31 248 282 72
51.0 271 296 127 8 11 24 262 339 50
49.5 236 280 137 10 10 22 252 302 57
48.0 349 370 145 11 18 41 315 412 67
46.5 235 283 78 7 11 22 214 297 45
45.0 210 252 85 7 5 21 216 258 40
43.5 203 241 103 9 10 22 194 260 52
42.0 266 314 141 12 10 28 272 329 70
40.5 136 179 65 3 6 17 148 171 35
39.0 139 203 54 6 10 7 166 173 34
37.5 126 170 84 3 6 15 138 155 63
36.0 190 246 83 8 8 16 206 229 52
34.5 94 108 31 2 4 5 93 105 24
33.0 81 106 38 5 4 7 81 104 24
31.5 78 97 31 3 3 3 79 99 19
30.0 113 145 70 5 9 12 125 136 41
28.5 45 62 23 1 1 5 50 58 15
27.0 42 66 13 5 48 57 11
25.5 22 38 9 1 1 3 24 32 8
24.0 67 94 38 1 1 7 74 77 39
22.5 18 33 12 1 24 30 8
21.0 17 25 12 1 4 19 26 4
19.5 15 24 4 1 1 1 17 17 6
18.0 35 48 15 1 3 4 30 44 16
16.5 3 10 2 6 8 1
15.0 6 5 4 1 6 4 4
13.5 2 8 3 3 6 4
12.0 21 23 5 3 17 25 4
10.5 2 1 2 1
9.0 3 1 1 1
7.5 1 2 2 1
6.0 5 3 3 3 6 2
4.5 1 1
3.0 1 1
1.5
1 1
American Mathematics Competitions
SCORE DISTRIBUTION
2011 AMC 12 B Results
GENDER and GRADES
score ----gender------------ ---------------------------grade---------------------------
male female ? <=6 7 8 9 10 11 12 13 ?
---------------------------- -----------------------------------------------------------
150.0 4 1 2 1 2
148.5
147.0
145.5 6 3 1 1 3 1 3
144.0 8 1 1 1 1 4 3 1
142.5
141.0 1 2 1 2
139.5 2 8 1 1 1 7
138.0 8 1 1 1 2 4 1
136.5 8 1 4 1 3 1 4 1 3
135.0 11 8 1 2 6 2 8
133.5 4 1 2 2 1
132.0 26 1 6 1 1 2 11 13 5
130.5 10 3 1 1 9 2
129.0 11 3 3 3 5 1 5 3
127.5 11 1 3 1 8 3 3
126.0 29 3 18 9 15 11 15
124.5 13 1 6 1 3 8 4 4
123.0 25 8 7 2 2 5 15 13 3
121.5 33 8 5 2 6 23 13 2
120.0 37 3 10 1 1 12 20 7 9
118.5 32 10 11 1 2 3 9 25 7 6
117.0 41 7 16 1 4 7 27 14 11
115.5 43 3 16 1 1 3 12 18 11 16
114.0 73 16 24 1 11 14 48 26 13
112.5 43 8 20 3 4 12 28 14 10
111.0 48 16 20 2 5 10 39 15 13
109.5 71 19 17 5 14 43 28 1 16
108.0 102 19 30 1 4 9 18 64 37 1 17
106.5 88 19 35 1 9 15 58 34 1 24
105.0 102 30 23 4 8 12 74 39 18
103.5 95 21 25 3 10 19 56 36 17
102.0 146 48 48 3 5 6 23 109 67 29
100.5 134 42 39 5 7 23 102 57 1 20
99.0 131 47 40 4 3 9 33 81 68 1 19
97.5 114 37 46 4 10 24 90 41 1 27
96.0 169 59 59 3 4 11 23 119 86 2 39
94.5 202 77 72 3 6 13 43 148 110 28
93.0 178 50 49 5 6 9 33 120 78 1 25
91.5 201 70 71 1 4 10 37 157 99 1 33
90.0 276 70 100 2 5 20 36 192 142 2 47
88.5 267 88 95 2 5 4 21 49 209 128 32
87.0 215 85 90 1 2 2 13 43 181 109 1 38
85.5 213 93 93 1 2 3 19 44 177 117 1 35
84.0 302 103 115 2 1 6 13 53 231 145 1 68
82.5 317 95 106 6 5 24 63 205 180 3 32
81.0 296 122 111 1 7 19 61 219 179 3 40
79.5 254 114 87 1 3 10 32 202 158 2 47
78.0 358 152 168 8 23 50 263 240 3 91
76.5 350 159 130 1 2 5 19 67 270 208 3 64
75.0 329 162 116 1 5 19 49 289 190 6 48
73.5 327 155 118 1 2 14 51 276 198 3 55
72.0 449 206 163 3 2 5 20 57 374 273 4 80
70.5 373 203 140 2 3 5 15 60 325 235 5 66
69.0 381 202 146 5 25 44 326 263 3 63
67.5 396 243 141 4 20 58 355 270 3 70
66.0 533 278 192 6 19 66 486 315 1 110
64.5 407 235 162 5 5 24 67 367 271 2 63
63.0 363 281 165 1 2 2 24 57 361 279 5 78
61.5 411 286 157 9 26 49 399 294 3 74
60.0 519 351 217 1 6 22 71 491 372 2 122
58.5 394 322 131 4 3 18 51 395 300 2 74
57.0 373 346 154 1 2 5 16 45 427 312 1 64
55.5 415 341 151 2 5 4 22 64 429 304 1 76
54.0 483 422 190 1 2 1 23 76 510 371 4 107
52.5 384 302 141 1 4 24 57 385 291 1 64
51.0 325 342 139 1 2 27 51 382 263 1 79
49.5 327 334 128 1 3 14 58 410 249 2 52
48.0 414 413 158 1 6 22 76 458 332 90
46.5 287 358 115 6 12 42 421 228 1 50
45.0 267 326 111 2 3 17 47 361 218 1 55
43.5 263 305 91 2 2 20 50 345 207 1 32
42.0 312 354 145 2 1 28 43 395 266 3 73
40.5 178 229 78 2 1 17 31 229 170 35
39.0 171 192 58 2 10 31 217 135 1 25
37.5 145 185 86 2 6 26 199 137 46
36.0 201 231 99 1 1 12 33 253 164 1 66
34.5 86 118 39 1 11 17 124 77 13
33.0 85 92 32 2 7 21 93 72 14
31.5 64 79 27 5 9 78 61 17
30.0 119 135 38 1 1 7 12 125 119 27
28.5 29 52 20 2 4 8 47 27 13
27.0 26 34 8 3 1 32 22 10
25.5 26 30 9 1 3 35 22 4
24.0 53 41 25 1 5 63 35 15
22.5 11 17 5 1 1 17 11 3
21.0 13 9 1 1 2 16 2 2
19.5 10 14 3 1 1 11 12 2
18.0 13 26 10 3 26 15 5
16.5 5 2 4 1 2 7 1
15.0 7 3 3 5 2
13.5 6 1 5 1 1
12.0 7 6 3 1 7 7 1
10.5 1 2 3
9.0 2 1 1
7.5 1 3 1 3 1 1
6.0 2 2 1 1 3 1
4.5
3.0
1.5
1 1
American Mathematics Competitions
Analysis
2011 AMC 10 A Results
Table of Item Difficulty for the 2011
Tabulation of responses for all Participants
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.43 0.61 11.48 84.97* 1.67 0.84 0.01
2 0.36 0.69 1.03 10.35 87.13* 0.41 0.03
3 1.68 4.15 5.84 60.97* 2.94 24.39 0.03
4 58.63* 5.41 6.72 5.00 3.46 20.75 0.03
5 3.88 18.43 55.88* 3.22 2.05 16.50 0.04
6 12.86 10.95 31.27* 17.20 4.52 23.15 0.05
7 5.18 40.38* 44.64 1.32 1.50 6.96 0.02
8 4.74 18.76 61.63* 2.08 2.66 10.11 0.02
9 33.85* 7.43 4.80 5.26 6.28 42.35 0.04
10 5.37 24.77* 5.95 12.24 13.63 38.01 0.03
11 8.35 28.64* 5.93 6.64 3.03 47.38 0.03
12 70.56* 2.41 3.46 6.44 2.71 14.39 0.03
13 28.78* 12.36 12.42 9.38 3.84 33.17 0.05
14 13.07 29.40* 11.96 3.51 3.06 38.97 0.03
15 4.98 6.56 32.34* 4.76 2.54 48.81 0.02
16 16.40 15.68* 3.73 4.38 18.71 41.07 0.03
17 1.65 2.98 65.56* 2.63 1.30 25.86 0.02
18 5.90 4.35 19.35* 11.96 6.49 51.91 0.04
19 5.01 7.14 6.20 4.40 9.39* 67.82 0.03
20 11.08 4.21 8.80 8.93* 11.75 55.17 0.05
21 6.07 6.13 8.32 6.93* 8.35 64.16 0.03
22 4.20 9.00 7.49* 6.11 6.58 66.58 0.03
23 6.60 5.10 18.46* 7.59 8.08 54.11 0.05
24 2.02 3.86 4.77 3.45* 2.72 83.15 0.02
25 2.51 4.08 4.06* 3.98 2.26 83.10 0.02
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses for all Participants
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.32 0.42 7.98 89.73* 1.02 0.52 0.01
2 0.07 0.13 0.65 0.38 98.64* 0.12 0.01
3 0.24 0.52 0.94 7.89 90.10* 0.28 0.03
4 2.26 12.28 73.20* 2.17 1.34 8.73 0.02
5 4.04 14.43 71.92* 1.47 2.10 6.03 0.02
6 81.30* 1.58 2.39 4.48 1.57 8.67 0.02
7 4.86 33.11* 6.28 11.81 11.23 32.68 0.04
8 1.00 2.12 79.88* 1.89 0.91 14.19 0.01
9 5.81 20.35* 8.10 9.21 28.81 27.67 0.04
10 15.17 42.20* 11.63 3.45 2.49 25.03 0.02
11 5.07 4.08 29.21* 17.32 8.34 35.94 0.04
12 4.99 6.35 5.26 18.78* 25.99 38.57 0.05
13 34.67 8.25* 4.52 10.90 2.84 38.80 0.02
14 3.03 5.92 5.52 5.73 9.01* 70.75 0.03
15 11.00* 3.29 15.75 4.07 2.38 63.48 0.03
16 3.55 10.18 8.11* 6.15 7.85 64.13 0.04
17 3.51 4.73 5.65 11.38* 4.72 69.98 0.03
18 3.92 5.59 10.95 24.59* 2.22 52.70 0.04
19 5.07 4.72 9.74* 2.88 1.55 75.99 0.04
20 6.04 11.86 6.83* 3.52 2.40 69.34 0.02
21 1.91* 3.52 3.41 3.54 2.31 85.28 0.03
22 2.12 3.63 4.19* 3.42 1.62 84.98 0.02
23 2.78 3.80 4.75* 2.88 2.07 83.68 0.03
24 4.25 6.07 6.56* 3.71 6.16 73.22 0.03
25 4.54 5.11 4.35 3.14* 9.94 72.88 0.03
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
American Mathematics Competitions
Analysis
2011 AMC 10 B Results
Table of Item Difficulty for the 2011
Tabulation of responses for all Participants
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 5.63 1.12 90.80* 0.85 0.21 1.39 0.00
2 12.27 2.58 3.59 3.59 75.74* 2.21 0.02
3 77.23* 5.90 3.90 4.59 1.68 6.70 0.01
4 5.79 5.14 65.07* 22.12 0.19 1.68 0.01
5 6.52 4.26 2.54 4.48 57.23* 24.94 0.04
6 78.61* 3.04 3.75 5.49 2.06 7.04 0.01
7 29.67 49.80* 5.36 2.59 4.64 7.92 0.01
8 24.70 67.46* 1.32 1.17 3.19 2.13 0.04
9 11.80 2.65 4.52 45.03* 3.23 32.75 0.02
10 10.68 43.38* 12.72 7.89 6.72 18.58 0.01
11 6.61 3.03 49.19 27.20* 3.45 10.50 0.02
12 40.04* 8.86 2.29 5.37 1.93 41.46 0.04
13 10.23 21.23 7.11 26.56* 8.05 26.80 0.01
14 6.67 6.89 44.52* 5.35 5.05 31.48 0.03
15 6.21 8.21 7.78 8.80 50.59* 18.34 0.06
16 30.32* 10.76 9.85 5.35 2.30 41.40 0.01
17 5.10 4.18 35.11* 9.66 11.15 34.77 0.02
18 1.77 5.34 18.68 20.52 27.08* 26.60 0.02
19 27.24* 10.46 3.70 7.27 11.25 40.02 0.06
20 4.27 16.96 16.53* 4.10 3.46 54.67 0.02
21 11.37 13.25* 6.21 5.31 3.06 60.78 0.03
22 6.96* 7.00 7.58 4.16 3.88 70.39 0.03
23 31.84 6.36 5.73 9.64* 4.08 42.29 0.05
24 7.94 4.98* 8.71 8.30 4.25 65.81 0.03
25 2.39 4.21 6.36 6.47* 4.42 76.15 0.01
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses for all Participants
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 2.50 0.82 95.12* 0.61 0.12 0.82 0.01
2 7.42 1.43 2.60 2.82 84.47* 1.23 0.03
3 3.89 5.06 73.42* 16.49 0.10 1.02 0.02
4 4.22 3.16 1.64 3.76 69.35* 17.80 0.06
5 48.44* 2.61 1.87 27.06 12.12 7.87 0.03
6 1.76 5.47 48.33* 5.16 10.02 29.18 0.07
7 8.12 60.76* 3.15 9.53 2.52 15.89 0.02
8 49.94* 7.83 2.92 5.13 1.64 32.48 0.06
9 9.74 14.76 6.77 44.25* 6.92 17.53 0.03
10 2.02 5.51 19.28 22.18 33.62* 17.33 0.06
11 9.63 32.70* 10.14 14.59 5.16 27.73 0.05
12 40.95* 8.56 11.06 5.57 2.17 31.65 0.03
13 10.96 18.85* 6.52 5.79 2.75 55.12 0.02
14 2.40 6.44 4.01 10.93* 8.69 67.48 0.05
15 11.09 13.08 9.05 14.42* 4.35 47.96 0.04
16 4.38 20.24 20.88* 4.36 2.92 47.19 0.03
17 2.73 14.60* 8.51 5.38 6.82 61.92 0.04
18 10.94* 5.85 8.41 4.38 4.43 65.96 0.04
19 8.58 6.38* 8.93 8.90 3.39 63.78 0.03
20 3.49 4.95 6.28* 4.97 3.21 77.05 0.05
21 3.94 5.54 6.83 7.42* 1.49 74.75 0.03
22 2.18 3.73 5.06 5.14* 3.04 80.81 0.05
23 4.57 6.25 9.75* 5.83 3.53 70.01 0.06
24 3.38 3.22* 4.38 4.20 3.41 81.37 0.04
25 3.41 5.66 4.67 3.83* 2.98 79.43 0.02
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
American Mathematics Competitions
Analysis
2011 AMC 10 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 35727 Student(s), Grade 10^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.43 0.55 10.88 85.95* 1.48 0.70 0.01
2 0.31 0.65 0.98 9.90 87.86* 0.29 0.02
3 1.38 3.88 5.28 65.52* 2.83 21.09 0.02
4 62.40* 4.57 6.33 4.51 3.39 18.76 0.03
5 3.29 16.21 60.54* 2.85 2.02 15.03 0.05
6 11.98 11.78 32.12* 17.43 4.87 21.77 0.06
7 3.76 45.79* 43.01 1.09 1.19 5.13 0.02
8 4.58 17.41 64.30* 1.97 2.61 9.11 0.03
9 37.76* 7.24 4.57 4.97 6.98 38.47 0.03
10 5.51 27.30* 5.67 12.29 13.06 36.15 0.02
11 8.67 32.82* 5.35 6.64 2.86 43.63 0.04
12 72.59* 2.12 3.07 6.00 2.55 13.65 0.02
13 29.86* 12.38 12.23 9.06 3.66 32.76 0.04
14 13.53 32.15* 11.41 3.45 2.89 36.54 0.04
15 4.57 5.89 35.08* 4.55 2.47 47.43 0.02
16 16.24 20.64* 3.33 4.15 18.78 36.83 0.04
17 1.48 2.62 67.83* 2.48 1.14 24.43 0.02
18 5.42 4.42 23.89* 12.38 6.60 47.25 0.04
19 4.93 7.05 6.06 4.44 9.26* 68.22 0.03
20 11.93 4.09 9.11 9.40* 11.95 53.44 0.07
21 5.78 6.16 8.29 6.67* 8.12 64.94 0.04
22 4.03 9.19 7.35* 6.19 6.73 66.48 0.02
23 6.48 4.99 19.62* 7.48 7.92 53.46 0.06
24 1.94 4.05 4.94 3.50* 2.81 82.72 0.03
25 2.32 4.09 4.18* 4.19 2.19 83.00 0.02
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 24410 Student(s), Grade 9^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.40 0.69 12.80 83.40* 1.83 0.88 0.00
2 0.44 0.74 1.10 11.31 85.89* 0.49 0.03
3 2.01 4.41 6.78 53.08* 3.10 30.59 0.03
4 51.24* 6.56 7.56 5.78 3.67 25.17 0.02
5 4.85 22.20 47.92* 3.74 2.01 19.27 0.01
6 13.86 10.43 27.85* 17.74 4.39 25.69 0.05
7 7.00 31.45* 49.11 1.62 1.66 9.15 0.01
8 5.17 21.30 56.79* 2.26 2.76 11.70 0.01
9 27.34* 7.79 5.19 5.74 5.67 48.24 0.04
10 5.29 19.93* 6.36 12.37 14.01 42.02 0.02
11 8.12 20.65* 6.75 6.69 3.42 54.35 0.02
12 67.12* 2.82 3.97 7.14 3.06 15.86 0.03
13 25.31* 11.92 12.79 9.95 4.24 35.75 0.05
14 12.43 23.81* 12.40 3.66 3.36 44.33 0.02
15 5.76 7.53 25.76* 5.18 2.72 53.03 0.02
16 17.01 8.87* 3.95 4.65 18.87 46.64 0.02
17 1.89 3.47 61.75* 2.83 1.44 28.61 0.01
18 6.53 4.29 11.44* 11.34 6.33 60.05 0.02
19 5.21 7.36 6.46 4.25 7.74* 68.95 0.03
20 9.51 4.45 8.59 7.68* 11.72 58.02 0.02
21 6.35 6.22 8.19 6.75* 8.19 64.28 0.02
22 4.38 8.25 7.38* 6.05 5.76 68.15 0.03
23 6.81 5.24 15.75* 7.49 8.34 56.33 0.04
24 1.97 3.64 4.40 3.15* 2.41 84.43 0.01
25 2.60 4.08 3.78* 3.58 2.22 83.74 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 5018 Student(s), Grades 8 and Below^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.26 0.26 6.82 90.85* 1.24 0.56 0.02
2 0.18 0.42 0.66 5.10 93.52* 0.10 0.02
3 1.22 4.40 3.47 76.52* 1.51 12.83 0.04
4 76.40* 3.65 4.30 3.67 2.79 9.15 0.04
5 2.25 11.78 70.23* 2.31 2.51 10.88 0.04
6 12.26 7.69 48.72* 11.74 2.31 17.20 0.08
7 5.38 53.39* 31.98 1.10 1.85 6.28 0.02
8 3.19 11.08 75.11* 1.63 2.25 6.70 0.04
9 44.36* 5.68 3.73 4.70 4.76 36.69 0.08
10 4.62 37.35* 4.20 10.24 16.50 27.02 0.06
11 6.10 48.01* 4.11 6.04 1.83 33.88 0.04
12 79.53* 1.77 2.33 5.46 1.59 9.29 0.02
13 44.70* 15.01 10.56 7.09 2.45 20.17 0.02
14 12.83 43.88* 11.34 2.63 2.47 26.80 0.04
15 2.69 5.16 52.03* 3.91 1.87 34.34 0.00
16 13.19 22.62* 4.30 4.50 16.44 38.92 0.02
17 1.08 2.27 74.95* 2.19 1.04 18.45 0.02
18 4.96 3.85 35.73* 10.40 5.82 39.22 0.02
19 4.18 6.40 5.26 4.70 20.84* 58.57 0.04
20 14.25 3.65 7.07 13.65* 9.90 51.39 0.08
21 5.50 5.22 9.25 10.18* 10.70 59.13 0.02
22 4.36 11.76 9.49* 5.18 9.90 59.23 0.08
23 5.98 5.10 27.46* 8.89 7.35 45.12 0.10
24 2.11 3.41 4.90 4.60* 3.13 81.83 0.02
25 2.07 4.05 4.13* 4.13 2.67 82.94 0.02
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 32739 Student(s), MALES
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.37 0.45 7.86 89.45* 1.22 0.65 0.01
2 0.24 0.62 0.82 8.14 89.88* 0.28 0.03
3 1.63 4.58 5.27 66.15* 2.27 20.07 0.03
4 66.04* 4.39 6.60 4.56 3.01 15.37 0.03
5 2.73 15.81 63.80* 2.75 1.98 12.87 0.05
6 11.47 10.74 36.95* 15.02 4.73 21.03 0.06
7 4.73 47.20* 39.97 1.17 1.40 5.49 0.02
8 3.74 15.60 68.26* 1.78 2.51 8.08 0.03
9 37.58* 7.41 4.41 5.23 6.06 39.26 0.05
10 4.97 28.43* 5.63 12.41 14.86 33.66 0.04
11 7.94 34.89* 5.42 6.89 2.84 42.00 0.02
12 77.27* 2.01 2.89 5.71 1.96 10.12 0.05
13 32.23* 12.80 12.66 8.94 3.54 29.77 0.05
14 13.31 35.71* 12.07 3.67 3.10 32.11 0.04
15 3.70 6.23 41.11* 4.87 2.84 41.23 0.02
16 14.87 19.22* 3.96 4.67 18.76 38.48 0.04
17 1.60 2.72 69.96* 2.48 1.18 22.05 0.02
18 5.43 4.20 24.07* 12.58 6.48 47.21 0.04
19 5.00 7.35 6.16 4.82 12.62* 64.00 0.04
20 12.18 4.47 8.83 10.99* 11.38 52.08 0.07
21 6.16 6.41 9.07 8.12* 9.00 61.20 0.04
22 4.11 9.93 8.14* 5.94 7.06 64.78 0.05
23 6.50 5.24 21.74* 8.09 8.16 50.20 0.07
24 2.23 4.28 5.36 4.14* 3.04 80.92 0.04
25 2.65 4.45 4.64* 4.34 2.48 81.43 0.01
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 25692 Student(s), Females
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.50 0.81 16.11 79.39* 2.21 0.97 0.01
2 0.49 0.75 1.19 13.00 84.07* 0.46 0.02
3 1.69 3.57 6.52 55.02* 3.79 29.39 0.02
4 50.76* 6.60 6.73 5.25 3.91 26.72 0.03
5 5.30 21.34 46.98* 3.75 2.21 20.40 0.02
6 14.41 11.24 24.46* 20.16 4.64 25.05 0.04
7 5.59 32.90* 49.98 1.58 1.60 8.33 0.01
8 6.07 22.36 54.11* 2.48 2.85 12.12 0.02
9 29.99* 7.52 5.28 5.41 6.82 44.95 0.02
10 6.03 22.10* 6.16 11.99 12.42 41.29 0.02
11 8.80 22.79* 6.48 6.16 3.22 52.52 0.04
12 63.04* 2.93 4.11 7.26 3.65 19.01 0.01
13 25.44* 11.66 12.02 9.99 4.31 36.54 0.04
14 12.63 22.69* 11.67 3.28 2.98 46.73 0.03
15 6.53 6.95 22.97* 4.71 2.19 56.64 0.01
16 18.09 14.50* 3.26 4.02 18.43 41.69 0.02
17 1.69 3.29 61.47* 2.77 1.42 29.35 0.02
18 6.45 4.68 16.43* 10.98 6.47 54.98 0.02
19 5.12 7.07 6.38 3.86 6.40* 71.14 0.02
20 10.29 3.95 8.82 6.76* 12.86 57.27 0.05
21 5.99 5.97 7.68 5.58* 7.84 66.92 0.02
22 4.41 8.33 7.10* 6.55 6.25 67.34 0.01
23 6.80 5.07 16.06* 7.12 8.09 56.84 0.04
24 1.81 3.58 4.32 2.85* 2.38 85.06 0.01
25 2.38 3.83 3.43* 3.85 2.11 84.39 0.01
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 12488 Student(s), Unknown Gender
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.43 0.62 11.43 84.71* 1.70 1.07 0.04
2 0.39 0.78 1.27 10.71 86.19* 0.62 0.03
3 1.77 4.24 5.96 59.65* 2.93 25.42 0.03
4 55.40* 5.65 6.99 5.64 3.71 22.59 0.02
5 3.97 19.31 53.40* 3.37 1.92 17.99 0.02
6 13.34 10.91 30.37* 16.82 3.73 24.78 0.05
7 5.52 37.86* 45.90 1.19 1.55 7.98 0.01
8 4.64 19.63 59.70* 2.04 2.66 11.31 0.02
9 32.00* 7.31 4.81 5.01 5.73 45.10 0.04
10 5.09 20.68* 6.35 12.28 12.92 42.66 0.02
11 8.53 24.30* 6.11 6.96 3.15 50.89 0.06
12 68.43* 2.41 3.59 6.69 2.75 16.10 0.03
13 26.59* 12.65 12.61 9.28 3.64 35.17 0.06
14 13.37 26.67* 12.26 3.56 3.13 40.98 0.03
15 5.14 6.62 28.60* 4.56 2.47 52.59 0.02
16 16.96 8.82* 4.08 4.37 19.12 46.58 0.06
17 1.72 3.05 62.44* 2.71 1.37 28.70 0.02
18 6.01 4.08 12.99* 12.35 6.58 57.91 0.07
19 4.80 6.72 5.95 4.44 7.08* 71.00 0.02
20 9.83 4.07 8.69 8.02* 10.45 58.93 0.02
21 6.01 5.75 7.65 6.56* 7.73 66.26 0.05
22 4.00 7.95 6.61* 5.66 5.98 69.76 0.04
23 6.49 4.80 14.77* 7.28 7.87 58.74 0.05
24 1.91 3.38 4.19 2.85* 2.59 85.07 0.02
25 2.41 3.63 3.81* 3.31 1.98 84.82 0.05
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 66 Student(s), Grade 13^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.00 0.00 7.58 89.39* 1.52 1.52 0.00
2 0.00 0.00 4.55 0.00 95.45* 0.00 0.00
3 1.52 0.00 1.52 4.55 92.42* 0.00 0.00
4 3.03 9.09 71.21* 9.09 0.00 7.58 0.00
5 4.55 18.18 69.70* 0.00 0.00 7.58 0.00
6 83.33* 1.52 1.52 4.55 0.00 9.09 0.00
7 6.06 36.36* 0.00 12.12 10.61 34.85 0.00
8 1.52 1.52 81.82* 0.00 0.00 15.15 0.00
9 4.55 24.24* 10.61 6.06 33.33 21.21 0.00
10 10.61 45.45* 13.64 1.52 3.03 25.76 0.00
11 3.03 4.55 34.85* 9.09 9.09 39.39 0.00
12 6.06 6.06 6.06 21.21* 22.73 37.88 0.00
13 22.73 13.64* 4.55 9.09 1.52 48.48 0.00
14 1.52 9.09 4.55 1.52 7.58* 75.76 0.00
15 7.58* 4.55 12.12 9.09 1.52 65.15 0.00
16 4.55 12.12 10.61* 7.58 7.58 57.58 0.00
17 1.52 6.06 4.55 10.61* 1.52 75.76 0.00
18 3.03 4.55 9.09 18.18* 3.03 62.12 0.00
19 3.03 12.12 6.06* 1.52 0.00 77.27 0.00
20 3.03 13.64 10.61* 3.03 0.00 69.70 0.00
21 0.00* 6.06 1.52 3.03 0.00 89.39 0.00
22 1.52 1.52 3.03* 3.03 3.03 87.88 0.00
23 3.03 1.52 3.03* 4.55 0.00 87.88 0.00
24 3.03 3.03 1.52* 0.00 7.58 84.85 0.00
25 1.52 3.03 3.03 1.52* 4.55 86.36 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 29957 Student(s), Grade 12^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.34 0.38 7.18 90.70* 0.93 0.45 0.01
2 0.05 0.15 0.69 0.41 98.59* 0.09 0.02
3 0.21 0.51 0.91 7.65 90.47* 0.22 0.03
4 1.94 10.94 75.45* 2.05 1.26 8.35 0.02
5 3.95 13.07 73.65* 1.42 2.13 5.77 0.02
6 82.51* 1.52 2.27 4.10 1.34 8.23 0.03
7 4.64 34.32* 6.29 11.54 10.65 32.51 0.05
8 1.00 2.03 80.19* 1.89 0.84 14.01 0.02
9 5.53 20.24* 7.77 8.99 28.97 28.45 0.05
10 14.43 44.78* 11.32 3.36 2.31 23.78 0.02
11 4.72 3.90 31.56* 17.77 8.33 33.67 0.05
12 5.08 6.35 5.08 18.74* 25.58 39.12 0.05
13 32.09 7.69* 5.02 10.93 2.75 41.49 0.03
14 3.10 5.75 5.64 5.76 9.76* 69.93 0.05
15 10.85* 3.59 15.31 3.82 2.37 64.04 0.04
16 3.46 10.11 8.40* 6.00 7.75 64.23 0.05
17 3.48 4.90 5.52 11.77* 4.81 69.48 0.05
18 3.71 5.34 11.13 25.02* 2.17 52.59 0.04
19 5.24 4.82 9.95* 2.87 1.57 75.50 0.04
20 5.73 12.04 7.18* 3.47 2.22 69.33 0.03
21 2.05* 3.61 3.66 3.44 2.30 84.92 0.03
22 2.18 3.73 4.37* 3.29 1.63 84.77 0.03
23 2.71 3.95 4.86* 2.78 2.01 83.64 0.05
24 4.14 5.82 6.76* 3.48 5.76 74.01 0.04
25 4.22 4.95 4.41 3.13* 8.83 74.42 0.04
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 34889 Student(s), Grade 11^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.29 0.38 8.45 89.38* 1.05 0.45 0.01
2 0.08 0.09 0.61 0.34 98.80* 0.08 0.00
3 0.22 0.52 0.97 7.79 90.23* 0.26 0.03
4 2.30 12.87 72.41* 2.14 1.40 8.87 0.02
5 4.14 15.06 71.13* 1.52 2.04 6.09 0.02
6 80.74* 1.61 2.39 4.66 1.66 8.91 0.02
7 5.01 32.39* 6.32 12.21 11.70 32.34 0.04
8 0.89 2.20 80.14* 1.84 0.91 14.00 0.01
9 5.99 20.05* 8.49 9.57 28.90 26.96 0.04
10 15.85 40.59* 11.70 3.55 2.68 25.60 0.03
11 5.19 4.24 28.08* 17.57 8.41 36.47 0.03
12 4.95 6.49 5.51 18.78* 26.55 37.67 0.05
13 36.62 8.76* 4.28 10.89 2.82 36.61 0.01
14 3.02 6.13 5.43 5.88 8.25* 71.27 0.01
15 11.15* 3.16 16.41 4.32 2.48 62.46 0.02
16 3.65 10.26 7.76* 6.25 8.22 63.81 0.04
17 3.52 4.79 5.91 11.38* 4.83 69.54 0.03
18 4.09 5.86 11.13 24.56* 2.30 52.03 0.03
19 5.07 4.73 9.53* 2.97 1.60 76.07 0.03
20 6.35 12.02 6.60* 3.74 2.55 68.74 0.01
21 1.83* 3.58 3.33 3.52 2.39 85.33 0.02
22 2.10 3.63 4.15* 3.56 1.63 84.90 0.03
23 2.88 3.76 4.78* 3.05 2.15 83.35 0.02
24 4.47 6.48 6.59* 3.82 6.52 72.09 0.02
25 4.80 5.39 4.40 3.17* 11.00 71.21 0.04
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 4469 Student(s), Grade 10^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.25 0.27 7.61 90.76* 0.81 0.31 0.00
2 0.02 0.09 0.47 0.20 99.04* 0.18 0.00
3 0.38 0.47 0.81 6.58 91.47* 0.25 0.04
4 2.69 12.58 72.59* 2.35 1.61 8.19 0.00
5 3.65 14.19 72.66* 1.23 2.04 6.22 0.02
6 82.77* 1.41 2.10 4.30 1.39 8.03 0.00
7 4.45 35.06* 5.68 10.85 11.59 32.36 0.00
8 1.25 1.59 80.89* 1.36 0.76 14.14 0.00
9 5.24 24.12* 6.82 7.63 28.46 27.72 0.00
10 14.32 42.81* 11.32 3.16 2.17 26.23 0.00
11 4.63 3.51 29.65* 13.83 7.09 41.24 0.04
12 4.18 6.02 4.61 19.22* 25.49 40.41 0.07
13 37.14 9.44* 3.09 11.14 2.73 36.43 0.02
14 2.44 4.99 4.83 4.54 10.49* 72.70 0.00
15 11.77* 2.30 14.84 3.49 1.83 65.76 0.00
16 3.18 9.71 8.59* 5.57 6.78 66.17 0.00
17 3.13 3.20 4.18 10.99* 3.78 74.71 0.00
18 3.47 4.32 9.89 24.70* 1.88 55.65 0.09
19 4.01 3.74 10.79* 1.86 1.14 78.47 0.00
20 4.61 11.12 6.51* 2.37 1.83 73.55 0.00
21 1.50* 2.26 2.42 3.22 1.52 89.06 0.02
22 1.14 2.66 3.13* 2.60 1.19 89.28 0.00
23 2.10 2.46 3.24* 2.17 1.92 88.10 0.00
24 3.71 4.59 5.48* 3.33 5.57 77.29 0.02
25 3.85 4.32 3.29 2.60* 9.69 76.26 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 1348 Student(s), Grade 9^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.22 0.45 9.12 88.65* 1.04 0.52 0.00
2 0.00 0.15 0.52 0.45 98.74* 0.15 0.00
3 0.22 0.22 1.19 8.16 89.91* 0.30 0.00
4 3.34 19.44 61.65* 2.08 1.34 12.09 0.07
5 3.49 18.32 67.28* 1.41 1.71 7.79 0.00
6 79.45* 1.56 2.37 4.82 2.60 9.20 0.00
7 4.53 31.75* 5.49 9.79 12.91 35.39 0.15
8 1.04 2.08 76.56* 1.78 0.82 17.73 0.00
9 6.16 22.77* 8.09 8.75 28.93 25.15 0.15
10 13.80 36.13* 12.09 3.41 2.23 32.34 0.00
11 5.86 3.26 23.29* 11.50 7.64 48.44 0.00
12 4.82 4.53 4.60 19.81* 25.52 40.73 0.00
13 35.76 7.72* 3.26 11.05 3.41 38.65 0.15
14 2.37 4.45 3.71 4.30 9.57* 75.59 0.00
15 10.46* 2.08 12.91 4.01 1.63 68.92 0.00
16 3.19 9.64 9.05* 5.79 6.90 65.43 0.00
17 2.82 3.34 4.75 10.53* 3.41 75.15 0.00
18 3.41 4.38 7.94 22.11* 2.37 59.79 0.00
19 4.08 3.12 10.24* 2.30 0.37 79.82 0.07
20 6.01 8.68 7.12* 2.97 1.78 73.37 0.07
21 2.08* 2.89 2.89 3.34 1.26 87.46 0.07
22 2.15 3.26 3.26* 3.34 1.34 86.65 0.00
23 2.08 3.41 3.64* 2.45 1.78 86.65 0.00
24 3.12 5.27 5.12* 4.08 5.93 76.41 0.07
25 4.60 4.15 3.64 2.82* 9.27 75.52 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 214 Student(s), Grades 8 and Below^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.47 0.93 7.94 85.98* 4.21 0.47 0.00
2 0.00 0.00 2.80 0.00 96.26* 0.93 0.00
3 0.00 0.47 0.47 7.94 90.19* 0.93 0.00
4 2.34 13.08 72.43* 3.27 1.40 7.48 0.00
5 3.74 14.02 73.36* 1.40 0.93 6.07 0.47
6 79.44* 2.80 1.40 6.07 3.74 6.54 0.00
7 5.14 45.79* 5.14 7.48 12.62 23.83 0.00
8 0.00 2.80 78.50* 3.74 2.34 12.62 0.00
9 3.74 32.71* 6.07 10.75 22.90 23.83 0.00
10 13.55 49.07* 11.21 1.87 1.87 22.43 0.00
11 6.07 2.80 44.86* 6.07 5.61 34.58 0.00
12 4.67 4.21 5.61 28.04* 22.43 34.11 0.93
13 21.96 18.69* 2.80 10.75 1.87 43.93 0.00
14 1.40 6.07 4.21 3.74 21.03* 63.55 0.00
15 17.76* 2.80 10.28 5.61 1.87 61.68 0.00
16 3.74 8.41 12.62* 8.41 7.48 59.35 0.00
17 4.67 4.21 3.74 20.09* 3.27 64.02 0.00
18 4.21 2.80 6.07 36.45* 0.47 50.00 0.00
19 3.27 1.40 24.30* 1.87 0.93 68.22 0.00
20 6.07 12.62 13.08* 3.27 2.34 62.62 0.00
21 3.74* 3.74 0.93 5.14 2.34 84.11 0.00
22 2.34 2.34 4.21* 3.74 1.87 85.51 0.00
23 0.93 2.80 7.01* 2.34 1.87 85.05 0.00
24 2.34 5.14 7.01* 6.54 2.34 76.64 0.00
25 6.54 3.74 3.27 3.74* 7.01 75.70 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 37477 Student(s), MALES
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.26 0.32 5.29 93.05* 0.75 0.32 0.01
2 0.05 0.13 0.68 0.39 98.67* 0.07 0.01
3 0.19 0.38 0.72 5.88 92.63* 0.18 0.02
4 1.54 10.04 79.30* 1.79 1.27 6.04 0.02
5 2.87 11.71 77.52* 1.30 1.97 4.61 0.02
6 86.07* 1.30 1.96 3.78 1.12 5.76 0.01
7 4.67 37.23* 6.05 12.06 11.83 28.13 0.04
8 0.88 1.86 83.62* 1.71 0.84 11.07 0.01
9 5.56 23.47* 8.24 9.12 26.62 26.96 0.04
10 14.73 49.57* 11.48 3.33 2.44 18.42 0.02
11 4.65 3.62 34.65* 17.65 8.81 30.57 0.05
12 5.44 6.61 5.39 21.83* 26.33 34.36 0.06
13 32.40 10.04* 4.71 11.67 2.69 38.47 0.02
14 3.28 6.53 5.98 6.28 11.60* 66.30 0.02
15 13.06* 3.76 16.11 4.09 2.63 60.33 0.03
16 3.58 10.99 9.13* 5.97 8.11 62.17 0.05
17 3.59 4.97 5.87 13.80* 5.03 66.72 0.02
18 3.45 5.25 11.84 28.35* 2.21 48.87 0.04
19 5.39 5.10 12.31* 3.15 1.69 72.33 0.04
20 5.80 13.35 7.98* 3.75 2.25 66.86 0.01
21 2.26* 3.79 3.83 4.01 2.39 83.71 0.02
22 2.29 3.87 4.79* 3.56 1.64 83.82 0.02
23 2.99 3.99 5.26* 3.08 2.20 82.46 0.02
24 4.11 6.15 6.59* 3.58 5.69 73.85 0.02
25 4.59 5.66 4.60 3.11* 8.85 73.15 0.03
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 26418 Student(s), Females
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.38 0.56 12.04 84.91* 1.42 0.67 0.02
2 0.12 0.10 0.62 0.35 98.70* 0.10 0.02
3 0.31 0.71 1.24 10.72 86.65* 0.34 0.04
4 3.19 15.94 64.14* 2.69 1.47 12.55 0.02
5 5.83 18.54 63.58* 1.73 2.23 8.06 0.03
6 74.75* 1.98 2.93 5.30 2.31 12.69 0.03
7 5.10 28.03* 6.41 11.56 10.80 38.06 0.05
8 1.11 2.43 75.11* 2.12 0.94 18.28 0.02
9 6.06 16.14* 7.86 9.27 32.42 28.20 0.05
10 15.66 32.09* 11.50 3.52 2.65 34.55 0.04
11 5.56 4.81 22.25* 16.62 7.78 42.95 0.03
12 4.45 6.02 5.22 15.24* 25.50 43.52 0.05
13 38.25 6.96* 4.20 10.01 3.03 37.52 0.03
14 2.63 5.04 4.89 4.95 5.49* 76.97 0.03
15 8.51* 2.63 15.67 4.22 2.09 66.86 0.03
16 3.57 9.32 6.93* 6.40 7.87 65.86 0.04
17 3.38 4.57 5.46 9.09* 4.43 73.04 0.05
18 4.65 6.02 9.96 20.29* 2.33 56.72 0.04
19 4.77 4.11 6.44* 2.57 1.39 80.69 0.04
20 6.50 10.27 5.46* 3.32 2.60 71.84 0.02
21 1.46* 3.30 2.82 2.97 2.12 87.30 0.04
22 1.85 3.35 3.44* 3.25 1.67 86.41 0.03
23 2.57 3.58 4.07* 2.82 1.93 85.00 0.04
24 4.50 6.38 6.67* 3.93 6.91 71.56 0.04
25 4.65 4.55 4.04 3.16* 12.24 71.31 0.04
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 A Results
Table of Item Difficulty for the 2011
Tabulation of responses by 10770 Student(s), Unknown Gender
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.38 0.42 7.41 90.00* 0.95 0.84 0.01
2 0.06 0.19 0.63 0.44 98.39* 0.29 0.00
3 0.26 0.52 0.97 7.97 89.77* 0.50 0.01
4 2.47 11.12 74.21* 2.23 1.30 8.67 0.00
5 3.68 13.82 72.87* 1.43 2.22 5.97 0.02
6 80.77* 1.52 2.53 4.90 1.31 8.92 0.05
7 4.90 31.23* 6.78 11.58 10.19 35.29 0.03
8 1.15 2.27 78.54* 1.98 1.07 14.98 0.01
9 6.09 19.84* 8.23 9.35 27.60 28.87 0.02
10 15.50 41.32* 12.48 3.70 2.30 24.70 0.00
11 5.36 3.90 27.34* 17.88 8.10 37.42 0.01
12 4.76 6.25 4.94 16.87* 26.06 41.10 0.02
13 33.80 5.16* 4.61 10.39 2.92 43.10 0.02
14 3.15 5.98 5.47 5.77 8.63* 70.99 0.02
15 9.97* 3.28 14.71 3.64 2.25 66.15 0.01
16 3.40 9.45 7.45* 6.14 6.85 66.69 0.02
17 3.57 4.26 5.33 8.60* 4.39 73.82 0.04
18 3.76 5.75 10.32 22.06* 1.96 56.14 0.02
19 4.71 4.94 8.91* 2.73 1.42 77.22 0.06
20 5.76 10.60 6.17* 3.18 2.44 71.84 0.02
21 1.81* 3.14 3.37 3.31 2.52 85.82 0.04
22 2.20 3.51 3.90* 3.38 1.46 85.54 0.01
23 2.61 3.65 4.61* 2.37 2.01 84.72 0.05
24 4.13 5.00 6.21* 3.61 5.93 75.10 0.01
25 4.09 4.55 4.24 3.21* 8.09 75.79 0.02
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 16661 Student(s), Grade 10^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 4.75 0.98 92.10* 0.81 0.20 1.15 0.00
2 14.51 2.63 3.64 3.73 73.34* 2.14 0.02
3 77.67* 5.78 3.66 4.31 1.68 6.89 0.01
4 5.52 4.86 67.98* 19.98 0.19 1.48 0.01
5 6.62 4.12 2.59 4.86 56.46* 25.31 0.05
6 78.70* 2.83 3.79 6.12 2.05 6.49 0.01
7 28.85 50.36* 5.47 2.75 4.72 7.83 0.02
8 23.61 68.51* 1.27 1.21 3.15 2.20 0.05
9 11.66 2.38 3.89 49.89* 2.87 29.29 0.01
10 10.62 44.32* 12.76 8.12 6.40 17.78 0.00
11 6.37 3.20 49.71 27.06* 3.31 10.34 0.02
12 44.96* 8.19 2.21 4.55 1.83 38.23 0.03
13 11.24 21.85 7.36 27.50* 7.72 24.31 0.02
14 6.57 7.03 45.29* 5.34 4.93 30.82 0.02
15 6.01 7.38 7.42 8.19 54.11* 16.83 0.06
16 33.73* 9.78 10.17 4.64 2.23 39.44 0.01
17 5.05 3.82 38.86* 9.14 11.25 31.87 0.02
18 1.97 5.05 17.51 19.93 30.86* 24.64 0.03
19 31.38* 11.18 3.54 6.90 11.61 35.32 0.07
20 4.26 17.43 18.11* 4.34 3.25 52.59 0.02
21 11.97 13.48* 6.54 5.49 3.21 59.30 0.02
22 7.75* 7.68 7.93 4.24 4.14 68.23 0.04
23 31.64 6.55 5.81 9.44* 4.50 42.01 0.05
24 9.24 4.85* 9.36 9.05 4.28 63.17 0.05
25 2.46 4.36 6.77 7.11* 4.94 74.35 0.01
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 10249 Student(s), Grade 9^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 7.87 1.36 87.80* 1.00 0.25 1.71 0.00
2 10.41 2.72 4.11 4.06 76.10* 2.58 0.02
3 75.37* 6.07 4.41 5.06 1.76 7.33 0.00
4 7.09 5.03 58.43* 27.21 0.20 2.04 0.00
5 6.81 4.52 2.45 4.17 53.53* 28.51 0.02
6 75.76* 3.79 4.02 5.10 2.24 9.07 0.01
7 32.18 45.98* 5.71 2.33 4.76 9.03 0.01
8 28.52 63.45* 1.40 0.91 3.48 2.23 0.01
9 13.16 2.94 4.80 36.17* 3.76 39.16 0.02
10 10.99 36.76* 13.58 8.45 7.45 22.72 0.04
11 7.49 3.00 50.67 23.03* 3.73 12.08 0.01
12 29.12* 9.66 2.38 6.27 2.19 50.31 0.08
13 9.53 22.67 6.58 21.53* 8.60 31.08 0.02
14 7.32 7.21 38.66* 5.22 5.19 36.37 0.03
15 7.40 8.48 7.92 10.82 41.94* 23.38 0.07
16 21.94* 12.38 8.96 6.54 2.21 47.96 0.01
17 5.06 4.50 28.12* 9.83 10.99 41.51 0.00
18 1.50 5.85 20.61 21.67 20.26* 30.10 0.01
19 18.74* 10.06 3.95 7.80 9.98 49.46 0.01
20 4.41 13.81 13.07* 3.52 3.91 61.25 0.02
21 10.13 11.04* 5.65 4.90 2.67 65.59 0.03
22 4.49* 5.67 6.22 3.92 3.45 76.23 0.02
23 32.72 5.98 4.80 7.78* 3.62 45.07 0.04
24 6.14 4.57* 7.27 6.95 4.17 70.91 0.00
25 2.14 3.48 5.31 4.87* 3.54 80.66 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 3477 Student(s), Grades 8 and Below^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 3.31 0.95 93.93* 0.63 0.14 1.04 0.00
2 5.46 1.87 2.44 2.10 87.20* 0.92 0.00
3 83.81* 5.35 2.88 3.51 0.86 3.60 0.00
4 3.85 6.27 69.31* 19.13 0.06 1.35 0.03
5 3.62 3.13 1.90 3.05 73.43* 14.84 0.03
6 87.89* 1.67 2.01 3.57 1.38 3.48 0.00
7 29.48 57.81* 3.16 1.73 2.67 5.12 0.03
8 20.53 73.94* 0.98 1.21 2.04 1.27 0.03
9 9.35 3.05 6.50 43.17* 3.88 33.97 0.09
10 9.52 57.18* 9.95 5.90 5.67 11.79 0.00
11 5.12 2.16 47.11 35.15* 2.76 7.68 0.03
12 42.42* 9.58 2.62 6.15 1.67 37.53 0.03
13 7.13 13.86 7.39 34.45* 7.74 29.42 0.00
14 5.21 5.55 57.75* 4.08 5.35 22.06 0.00
15 4.14 10.64 8.77 6.27 56.80* 13.29 0.09
16 33.42* 11.22 10.32 5.61 2.93 36.50 0.00
17 4.72 4.75 33.25* 12.31 11.25 33.68 0.06
18 1.15 5.09 18.29 21.63 24.62* 29.22 0.00
19 28.93* 8.86 2.82 6.64 12.71 39.95 0.09
20 3.48 22.95 15.19* 3.80 3.42 51.11 0.06
21 8.92 15.27* 5.64 5.75 3.19 61.23 0.00
22 8.14* 5.49 8.34 4.14 3.62 70.26 0.00
23 30.37 6.50 7.39 13.55* 3.36 38.77 0.06
24 5.72 5.26* 7.91 8.23 3.97 68.88 0.03
25 1.78 3.88 6.10 6.15* 3.65 78.43 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 15097 Student(s), MALES
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 4.60 1.04 92.06* 0.97 0.15 1.18 0.00
2 9.62 2.33 3.52 3.62 79.13* 1.77 0.01
3 79.48* 5.88 3.60 3.71 1.68 5.64 0.01
4 4.34 5.48 66.52* 21.92 0.19 1.54 0.00
5 5.59 3.82 2.25 4.23 62.65* 21.40 0.05
6 82.02* 2.72 2.80 5.01 1.68 5.78 0.00
7 30.32 51.88* 5.14 2.25 3.98 6.41 0.02
8 19.63 73.02* 1.20 1.22 2.85 2.06 0.03
9 11.95 2.76 4.79 48.03* 2.97 29.49 0.02
10 9.47 51.28* 11.25 7.48 5.95 14.56 0.01
11 5.35 2.62 49.14 31.25* 2.99 8.62 0.03
12 43.31* 8.29 2.60 5.55 2.16 38.02 0.07
13 11.04 19.61 7.43 31.29* 7.48 23.14 0.02
14 6.58 6.68 49.04* 4.84 5.11 27.73 0.02
15 5.57 7.92 7.52 8.43 53.84* 16.67 0.05
16 33.91* 11.05 10.35 5.74 2.34 36.60 0.01
17 4.72 4.08 38.09* 9.74 11.31 32.04 0.03
18 1.77 5.27 17.98 20.14 29.77* 25.06 0.02
19 31.33* 9.78 3.49 6.82 11.37 37.14 0.07
20 4.54 18.30 18.53* 4.17 3.41 51.02 0.03
21 10.70 14.69* 6.51 6.08 3.35 58.64 0.03
22 8.25* 6.94 8.09 4.66 3.68 68.34 0.04
23 31.20 6.47 6.83 11.29* 3.76 40.37 0.07
24 8.39 5.37* 9.68 9.39 4.66 62.49 0.03
25 2.32 4.46 6.60 7.23* 4.96 74.43 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 12088 Student(s), Females
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 7.34 1.28 88.74* 0.79 0.29 1.56 0.00
2 16.31 3.03 3.80 3.77 70.40* 2.66 0.03
3 73.68* 6.11 4.25 5.77 1.69 8.49 0.01
4 7.92 4.57 62.52* 22.82 0.19 1.97 0.02
5 7.54 4.92 2.71 4.67 50.02* 30.10 0.02
6 73.99* 3.62 4.96 6.06 2.54 8.81 0.02
7 29.44 46.27* 5.93 2.96 5.18 10.20 0.02
8 31.74 59.75* 1.34 1.10 3.75 2.29 0.03
9 11.74 2.63 4.31 40.34* 3.88 37.09 0.01
10 12.22 32.54* 14.32 8.70 7.80 24.41 0.01
11 8.42 3.42 50.37 20.59* 3.92 13.27 0.01
12 34.55* 9.86 1.94 4.91 1.73 46.99 0.02
13 9.39 23.93 6.49 19.54* 8.57 32.06 0.02
14 7.03 7.42 38.63* 5.71 4.96 36.23 0.02
15 7.30 8.25 7.86 9.74 45.39* 21.38 0.08
16 24.46* 10.99 8.98 4.83 2.30 48.43 0.01
17 5.40 4.51 30.97* 9.65 10.68 38.77 0.02
18 1.80 5.58 19.68 21.43 22.96* 28.53 0.02
19 21.79* 11.66 3.91 7.78 10.65 44.18 0.03
20 4.01 14.98 13.54* 3.76 3.58 60.12 0.00
21 11.84 10.99* 5.61 4.45 2.61 64.49 0.02
22 5.27* 6.51 6.55 3.57 4.03 74.05 0.02
23 32.88 6.37 4.29 7.26* 4.54 44.64 0.03
24 6.92 4.19* 7.35 6.73 3.92 70.86 0.03
25 2.36 3.56 5.70 5.20* 3.68 79.50 0.01
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 10 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 6538 Student(s), Unknown Gender
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 4.83 1.02 91.68* 0.70 0.20 1.56 0.00
2 10.92 2.34 3.40 3.20 77.76* 2.37 0.02
3 78.59* 5.57 3.92 4.42 1.67 5.84 0.00
4 5.23 5.38 66.46* 21.26 0.21 1.45 0.00
5 6.78 4.04 2.89 4.70 58.00* 23.57 0.03
6 79.28* 2.72 3.75 5.54 2.05 6.67 0.00
7 28.59 51.53* 4.82 2.69 5.17 7.20 0.00
8 23.40 68.86* 1.58 1.18 2.94 1.99 0.06
9 11.58 2.46 4.28 46.77* 2.62 32.23 0.06
10 10.66 45.21* 13.15 7.33 6.52 17.10 0.03
11 6.18 3.27 47.12 30.09* 3.61 9.71 0.02
12 42.66* 8.35 2.22 5.81 1.76 39.19 0.02
13 9.91 20.01 7.53 28.63* 8.41 25.51 0.00
14 6.24 6.41 44.97* 5.87 5.08 31.39 0.05
15 5.67 8.78 8.23 7.92 52.72* 16.61 0.06
16 32.84* 9.67 10.31 5.41 2.22 39.52 0.03
17 5.45 3.81 35.88* 9.48 11.65 33.71 0.02
18 1.74 5.05 18.42 19.72 28.49* 26.57 0.02
19 27.88* 9.83 3.79 7.37 12.07 38.99 0.06
20 4.10 17.56 17.42* 4.56 3.33 53.00 0.03
21 12.05 14.09* 6.61 5.12 3.23 58.86 0.05
22 7.13* 8.01 8.31 4.10 4.07 68.37 0.02
23 31.37 6.10 5.89 10.22* 3.98 42.40 0.05
24 8.79 5.52* 8.98 8.69 3.88 64.12 0.02
25 2.60 4.83 7.04 7.07* 4.51 73.92 0.03
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 86 Student(s), Grade 13^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 0.00 0.00 97.67* 2.33 0.00 0.00 0.00
2 3.49 0.00 2.33 1.16 93.02* 0.00 0.00
3 2.33 5.81 84.88* 6.98 0.00 0.00 0.00
4 0.00 1.16 0.00 2.33 83.72* 12.79 0.00
5 63.95* 0.00 1.16 23.26 8.14 3.49 0.00
6 2.33 3.49 54.65* 4.65 6.98 27.91 0.00
7 2.33 76.74* 2.33 10.47 1.16 6.98 0.00
8 70.93* 4.65 2.33 2.33 1.16 18.60 0.00
9 8.14 12.79 2.33 62.79* 4.65 9.30 0.00
10 1.16 5.81 15.12 23.26 25.58* 29.07 0.00
11 8.14 36.05* 6.98 11.63 4.65 32.56 0.00
12 52.33* 8.14 5.81 6.98 4.65 22.09 0.00
13 12.79 9.30* 6.98 2.33 2.33 66.28 0.00
14 0.00 2.33 3.49 8.14* 6.98 79.07 0.00
15 4.65 6.98 9.30 10.47* 6.98 61.63 0.00
16 5.81 20.93 12.79* 3.49 4.65 52.33 0.00
17 6.98 10.47* 3.49 3.49 9.30 66.28 0.00
18 4.65* 6.98 9.30 0.00 5.81 73.26 0.00
19 6.98 6.98* 6.98 1.16 2.33 75.58 0.00
20 2.33 3.49 4.65* 1.16 1.16 87.21 0.00
21 2.33 3.49 2.33 3.49* 3.49 84.88 0.00
22 2.33 1.16 3.49 1.16* 2.33 89.53 0.00
23 5.81 3.49 9.30* 1.16 1.16 79.07 0.00
24 5.81 2.33* 2.33 2.33 0.00 87.21 0.00
25 0.00 5.81 3.49 1.16* 1.16 88.37 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 9959 Student(s), Grade 12^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 2.29 0.91 95.17* 0.74 0.12 0.76 0.00
2 5.95 1.63 2.68 3.26 85.22* 1.24 0.02
3 3.49 4.97 73.48* 16.91 0.12 0.98 0.04
4 4.01 3.26 1.83 3.82 68.39* 18.65 0.05
5 47.85* 2.52 1.75 27.13 12.14 8.60 0.02
6 1.82 6.02 43.80* 5.60 10.00 32.68 0.07
7 8.19 60.48* 2.93 9.65 2.61 16.12 0.02
8 47.15* 8.41 3.35 5.39 1.85 33.79 0.05
9 10.32 13.76 6.68 44.57* 6.99 17.65 0.03
10 2.18 6.37 19.46 23.13 29.87* 18.92 0.07
11 9.32 32.37* 9.93 14.75 5.51 28.10 0.02
12 37.18* 8.66 11.29 6.43 2.25 34.15 0.05
13 9.90 17.64* 6.57 4.98 2.40 58.47 0.04
14 2.63 6.45 4.07 9.20* 8.28 69.31 0.06
15 10.60 12.32 8.20 13.10* 4.26 51.45 0.06
16 4.16 18.57 18.56* 4.47 3.07 51.11 0.07
17 2.85 12.68* 8.33 5.59 6.68 63.83 0.03
18 9.34* 5.73 8.07 4.53 4.38 67.93 0.02
19 8.36 6.50* 8.46 8.12 3.47 65.05 0.03
20 3.34 5.09 5.65* 4.92 3.16 77.76 0.07
21 4.10 5.63 6.60 6.24* 1.57 75.86 0.01
22 2.54 3.70 5.01 4.68* 2.97 81.06 0.04
23 4.72 6.38 9.16* 5.76 3.33 70.59 0.06
24 3.38 3.23* 4.26 4.11 3.39 81.58 0.04
25 3.68 5.16 4.51 3.95* 3.10 79.57 0.04
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 14251 Student(s), Grade 11^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 2.80 0.86 94.89* 0.59 0.13 0.72 0.01
2 7.89 1.40 2.63 2.83 84.04* 1.18 0.02
3 4.39 5.11 71.59* 17.77 0.09 1.03 0.01
4 4.63 3.26 1.62 3.61 68.28* 18.53 0.07
5 46.96* 2.60 1.75 28.12 12.57 7.96 0.03
6 1.80 5.49 47.31* 5.17 10.72 29.44 0.08
7 8.71 59.53* 3.22 9.82 2.57 16.13 0.04
8 48.34* 7.89 2.98 5.10 1.56 34.06 0.06
9 9.93 15.89 6.97 42.07* 7.38 17.73 0.03
10 1.88 5.21 20.41 22.55 32.90* 16.97 0.07
11 10.34 31.84* 10.20 14.34 4.99 28.25 0.05
12 39.84* 8.86 11.23 5.40 2.32 32.31 0.03
13 10.71 17.64* 6.55 6.34 2.88 55.87 0.01
14 2.27 6.23 3.82 10.93* 9.36 67.34 0.04
15 11.87 13.15 8.80 13.74* 4.32 48.09 0.04
16 4.45 20.55 20.47* 4.39 2.92 47.20 0.01
17 2.65 13.59* 8.57 5.19 6.76 63.19 0.05
18 10.32* 5.77 8.29 4.42 4.75 66.41 0.04
19 8.32 5.73* 8.58 9.20 3.42 64.70 0.04
20 3.56 4.81 5.86* 4.66 3.32 77.76 0.02
21 3.94 5.40 6.48 7.08* 1.55 75.51 0.04
22 2.11 3.58 4.79 4.76* 2.87 81.83 0.06
23 4.65 6.27 9.06* 5.82 3.50 70.65 0.05
24 3.35 2.95* 4.12 4.03 3.47 82.04 0.03
25 3.52 5.70 4.62 3.40* 2.93 79.83 0.01
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 2429 Student(s), Grade 10^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 2.26 0.41 95.97* 0.33 0.16 0.86 0.00
2 4.86 0.99 2.22 1.93 89.21* 0.78 0.00
3 3.95 5.27 74.85* 15.03 0.08 0.82 0.00
4 2.47 2.39 0.99 2.39 76.82* 14.90 0.04
5 55.70* 1.44 1.15 24.95 11.16 5.56 0.04
6 1.89 4.41 56.69* 3.87 8.23 24.91 0.00
7 6.75 67.68* 1.73 8.52 1.69 13.63 0.00
8 53.36* 6.42 2.14 4.78 1.52 31.78 0.00
9 7.53 12.02 5.31 51.67* 5.89 17.54 0.04
10 1.69 4.69 18.07 20.26 38.74* 16.55 0.00
11 8.40 35.73* 9.35 15.07 4.94 26.39 0.12
12 46.93* 7.62 9.47 4.53 1.19 30.26 0.00
13 11.32 24.17* 5.85 4.94 2.31 51.42 0.00
14 2.14 5.35 3.91 12.02* 7.29 69.21 0.08
15 10.62 13.75 10.37 16.51* 3.99 44.75 0.00
16 3.54 22.56 23.96* 3.42 3.21 43.31 0.00
17 2.51 18.81* 6.75 4.65 5.06 62.21 0.00
18 12.60* 5.80 7.49 3.09 3.46 67.52 0.04
19 7.66 6.92* 9.55 8.15 2.84 64.88 0.00
20 2.92 4.08 6.88* 3.91 2.59 79.58 0.04
21 3.01 4.49 6.67 8.73* 0.78 76.33 0.00
22 1.28 3.33 3.95 4.57* 2.55 84.27 0.04
23 3.75 4.69 11.07* 5.80 3.25 71.39 0.04
24 2.55 2.14* 4.36 3.38 2.51 85.06 0.00
25 2.22 5.02 4.41 3.05* 2.39 82.91 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 903 Student(s), Grade 9^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 3.65 0.78 94.02* 0.22 0.22 1.11 0.00
2 4.43 0.89 2.44 2.33 88.93* 0.89 0.11
3 3.54 5.98 72.65* 16.83 0.22 0.78 0.00
4 2.55 1.66 1.11 2.77 77.08* 14.84 0.00
5 60.91* 1.88 0.78 21.48 8.19 6.76 0.00
6 1.55 4.32 56.48* 3.54 9.08 24.92 0.11
7 5.20 67.44* 2.10 6.20 2.33 16.72 0.00
8 51.83* 6.87 1.66 5.43 1.22 32.89 0.11
9 5.87 12.85 6.53 48.17* 5.76 20.82 0.00
10 1.99 4.65 16.28 18.05 39.09* 19.93 0.00
11 7.20 34.55* 9.08 15.61 4.98 28.57 0.00
12 45.85* 7.42 10.30 4.98 1.44 30.01 0.00
13 10.96 25.03* 4.76 4.98 3.10 51.16 0.00
14 1.77 6.20 2.77 10.63* 6.20 72.31 0.11
15 7.86 15.17 11.30 17.28* 4.65 43.74 0.00
16 4.76 22.70 20.71* 3.21 1.33 47.29 0.00
17 2.21 18.72* 5.87 3.88 5.65 63.46 0.22
18 13.29* 5.20 6.76 2.44 2.77 69.44 0.11
19 7.09 6.64* 9.41 9.75 3.10 64.01 0.00
20 2.33 2.88 6.53* 3.43 2.33 82.39 0.11
21 2.44 5.43 5.09 8.86* 0.66 77.52 0.00
22 1.66 2.88 3.54 4.32* 2.55 85.05 0.00
23 2.99 5.54 11.85* 4.54 2.99 71.98 0.11
24 1.44 2.77* 3.77 2.88 1.55 87.38 0.22
25 1.44 3.65 3.10 3.99* 2.44 85.38 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 326 Student(s), Grades 8 and Below^
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 1.53 0.31 96.01* 0.92 0.61 0.61 0.00
2 2.15 0.61 3.07 0.92 92.64* 0.61 0.00
3 1.23 6.75 80.06* 11.66 0.00 0.31 0.00
4 0.92 1.23 0.92 2.76 84.97* 9.20 0.00
5 64.72* 1.53 0.92 21.17 9.20 2.45 0.00
6 1.23 3.37 67.18* 5.21 5.83 17.18 0.00
7 4.29 79.14* 3.07 6.44 0.61 6.44 0.00
8 64.72* 7.67 2.76 3.99 2.15 18.71 0.00
9 3.68 8.28 5.21 62.27* 5.52 15.03 0.00
10 2.15 4.29 12.27 24.85 44.17* 12.27 0.00
11 6.75 38.34* 8.90 17.48 7.67 20.86 0.00
12 57.98* 6.44 10.12 3.68 1.84 19.63 0.31
13 8.59 27.91* 7.67 6.44 1.84 47.55 0.00
14 1.84 3.37 6.13 15.95* 6.44 66.26 0.00
15 9.20 12.27 14.11 26.38* 4.29 33.74 0.00
16 5.52 28.53 27.30* 2.45 3.37 32.82 0.00
17 3.68 24.54* 5.21 4.91 7.98 53.68 0.00
18 16.26* 3.07 10.43 4.91 4.60 60.43 0.31
19 7.06 11.35* 10.12 9.82 1.84 59.51 0.31
20 2.76 5.21 7.36* 4.29 2.45 77.91 0.00
21 3.68 3.37 5.83 10.74* 1.53 74.85 0.00
22 2.15 2.76 3.99 6.44* 2.45 82.21 0.00
23 5.21 3.99 13.80* 5.52 3.68 67.79 0.00
24 1.84 3.99* 5.21 3.07 3.07 82.82 0.00
25 2.76 7.36 3.07 4.91* 0.31 81.60 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 15095 Student(s), MALES
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 1.96 0.79 95.81* 0.66 0.13 0.65 0.01
2 4.84 1.37 2.47 2.76 87.68* 0.86 0.02
3 2.89 5.17 75.66* 15.38 0.09 0.80 0.01
4 3.30 2.80 1.45 3.15 74.87* 14.39 0.04
5 52.90* 2.08 1.56 25.98 11.22 6.23 0.03
6 1.66 5.23 53.02* 5.09 9.65 25.30 0.07
7 6.91 68.10* 2.61 8.21 2.13 12.03 0.01
8 54.28* 7.60 3.23 5.00 1.52 28.30 0.07
9 9.90 12.50 6.46 51.45* 5.93 13.72 0.03
10 1.95 5.53 18.32 21.46 36.76* 15.91 0.06
11 8.35 37.37* 10.38 15.11 5.35 23.42 0.02
12 45.19* 8.27 11.46 5.66 2.13 27.25 0.03
13 10.22 22.03* 6.72 5.91 2.87 52.22 0.03
14 2.57 6.41 4.23 13.15* 8.53 65.06 0.06
15 10.79 13.92 10.04 15.14* 4.10 45.98 0.03
16 4.29 21.15 22.92* 4.55 2.80 44.27 0.03
17 3.07 17.86* 7.88 5.53 7.01 58.62 0.03
18 12.16* 5.75 8.74 3.93 4.54 64.86 0.02
19 8.79 7.19* 9.96 9.83 3.36 60.83 0.03
20 3.14 4.60 7.02* 4.87 3.11 77.24 0.03
21 3.73 5.57 6.73 8.07* 1.47 74.41 0.02
22 2.08 3.56 5.17 5.55* 3.20 80.40 0.04
23 4.39 6.00 10.84* 5.93 3.39 69.41 0.05
24 3.09 3.29* 4.74 4.18 3.05 81.62 0.03
25 3.29 5.45 5.05 3.90* 2.88 79.40 0.02
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 9987 Student(s), Females
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 3.73 0.93 93.84* 0.47 0.15 0.86 0.01
2 10.58 1.52 2.88 3.05 80.27* 1.65 0.03
3 5.88 4.83 67.62* 20.25 0.12 1.28 0.03
4 5.62 3.93 1.98 4.38 60.20* 23.80 0.10
5 41.35* 3.32 2.10 29.22 13.23 10.74 0.03
6 1.98 6.15 38.03* 5.52 11.24 36.99 0.09
7 10.41 48.62* 3.71 11.82 3.22 22.17 0.04
8 39.69* 8.44 2.74 5.46 1.81 41.81 0.04
9 9.53 18.79 7.15 31.73* 8.79 23.97 0.03
10 1.99 5.58 21.81 23.68 26.23* 20.62 0.09
11 12.18 25.13* 9.45 13.38 4.85 34.95 0.07
12 31.42* 9.18 10.56 5.39 2.30 41.11 0.03
13 11.23 13.07* 6.03 5.38 2.52 61.75 0.02
14 2.16 6.00 3.53 6.96* 8.63 72.66 0.05
15 11.64 11.42 7.14 12.90* 4.71 52.14 0.06
16 4.40 17.98 16.69* 3.94 3.23 53.73 0.03
17 2.26 8.74* 8.84 4.77 6.04 69.28 0.07
18 8.02* 5.73 7.22 4.83 4.37 69.77 0.07
19 7.34 4.59* 7.03 7.03 3.43 70.52 0.06
20 3.88 5.46 4.43* 4.60 3.31 78.25 0.08
21 4.23 5.42 6.36 5.71* 1.52 76.74 0.03
22 2.38 3.74 4.30 3.67* 2.57 83.27 0.06
23 5.04 6.35 7.68* 5.76 3.34 71.76 0.07
24 3.57 2.71* 3.54 3.76 3.98 82.37 0.06
25 3.92 5.57 4.05 3.29* 2.84 80.30 0.03
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.
American Mathematics Competitions
Analysis
2011 AMC 12 B Results
Table of Item Difficulty for the 2011
Tabulation of responses by 5764 Student(s), Unknown Gender
Percent of Responses
ITEM A B C D E OMITS ?
____ _____ _____ _____ _____ _____ _____ _____
1 1.79 0.71 95.52* 0.69 0.07 1.21 0.00
2 8.69 1.44 2.45 2.57 83.36* 1.46 0.03
3 3.05 5.20 77.60* 12.89 0.09 1.15 0.02
4 4.23 2.79 1.54 4.27 70.75* 16.34 0.07
5 49.06* 2.78 2.26 26.15 12.54 7.20 0.02
6 1.67 4.91 53.92* 4.75 8.90 25.82 0.03
7 7.32 62.60* 3.61 9.06 2.29 15.11 0.02
8 56.37* 7.37 2.43 4.88 1.65 27.26 0.05
9 9.66 13.71 6.90 47.07* 6.30 16.36 0.00
10 2.24 5.36 17.40 21.46 38.17* 15.35 0.02
11 8.55 33.61* 10.69 15.34 5.22 26.49 0.10
12 46.34* 8.22 10.90 5.66 2.06 26.79 0.03
13 12.44 20.54* 6.82 6.18 2.83 51.20 0.00
14 2.38 7.32 4.29 11.97* 9.21 64.82 0.02
15 10.91 13.76 9.80 15.18* 4.41 45.92 0.02
16 4.61 21.76 22.80* 4.61 2.67 43.51 0.03
17 2.65 16.19* 9.58 6.07 7.67 57.82 0.02
18 12.80* 6.30 9.63 4.77 4.23 62.25 0.02
19 10.18 7.36* 9.51 9.70 3.42 59.84 0.00
20 3.76 5.00 7.53* 5.86 3.31 74.48 0.05
21 4.01 5.69 7.91 8.71* 1.47 72.17 0.03
22 2.06 4.16 6.09 6.59* 3.42 77.64 0.03
23 4.23 6.77 10.48* 5.67 4.23 68.55 0.07
24 3.80 3.90* 4.89 5.03 3.38 78.96 0.03
25 2.85 6.38 4.74 4.58* 3.49 77.97 0.00
(*) Correct Response
(?) Response the computer was unable to read due to incomplete
erasures or two answers marked in the same column
(^) Note: Students who failed to indicate their grade are not
included in this analysis.