Math Main Page => Exercises - Math III
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Goal: to practice how to make use of distributive property on special numbers, like (A + B) * (A - B) = A*A - B*B, A*C +B*C = (A + B ) *C, A*C - B*C = (A-B) * C
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Friday November 13 2026
04:12:03 PM | Friday November 13 2026
04:12:03 PMFlip Answers |
| 1) | 97 * 103 = | | 1) 100 * 100 - 3 * 3 = 9991 |
| 2) | 407 * 393 = | | 2) 400 * 400 - 7 * 7 = 159951 |
| 3) | 290 * 310 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 408 * 392 = | | 4) 400 * 400 - 8 * 8 = 159936 |
| 5) | 399 * 401 = | | 5) 400 * 400 - 1 * 1 = 159999 |
| 6) | 403 * 397 = | | 6) 400 * 400 - 3 * 3 = 159991 |
| 7) | 202 * 198 = | | 7) 200 * 200 - 2 * 2 = 39996 |
| 8) | 398 * 402 = | | 8) 400 * 400 - 2 * 2 = 159996 |
| 9) | 193 * 207 = | | 9) 200 * 200 - 7 * 7 = 39951 |
| 10) | 390 * 410 = | | 10) 400 * 400 - 10 * 10 = 159900 |
| 11) | 240 * 23 - 23 * 40 = | | 11) ( 240 - 40) * 23 = 4600 |
| 12) | 30 * 166 - 30 * 66 = | | 12) ( 166 - 66) * 30 = 3000 |
| 13) | 272 * 97 - 97 * 72 = | | 13) ( 272 - 72) * 97 = 19400 |
| 14) | 249 * 91 - 49 * 91 = | | 14) ( 249 - 49) * 91 = 18200 |
| 15) | 146 * 23 + 54 * 23 = | | 15) ( 146 + 54) * 23 = 4600 |
| 16) | 50 * 38 + 50 * 62 = | | 16) ( 62 + 38) * 50 = 5000 |
| 17) | 26 * 92 + 92 * 74 = | | 17) ( 26 + 74) * 92 = 9200 |
| 18) | 94 * 59 + 94 * 41 = | | 18) ( 59 + 41) * 94 = 9400 |
| 19) | 271 * 42 - 71 * 42 = | | 19) ( 271 - 71) * 42 = 8400 |
| 20) | 159 * 30 - 30 * 59 = | | 20) ( 159 - 59) * 30 = 3000 |
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Score: ______________ | |
