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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Thursday May 21 2026
06:17:43 AM | Thursday May 21 2026
06:17:43 AMFlip Answers |
| 1) | 392 * 408 = | | 1) 400 * 400 - 8 * 8 = 159936 |
| 2) | 296 * 304 = | | 2) 300 * 300 - 4 * 4 = 89984 |
| 3) | 405 * 395 = | | 3) 400 * 400 - 5 * 5 = 159975 |
| 4) | 209 * 191 = | | 4) 200 * 200 - 9 * 9 = 39919 |
| 5) | 193 * 207 = | | 5) 200 * 200 - 7 * 7 = 39951 |
| 6) | 95 * 105 = | | 6) 100 * 100 - 5 * 5 = 9975 |
| 7) | 207 * 193 = | | 7) 200 * 200 - 7 * 7 = 39951 |
| 8) | 408 * 392 = | | 8) 400 * 400 - 8 * 8 = 159936 |
| 9) | 397 * 403 = | | 9) 400 * 400 - 3 * 3 = 159991 |
| 10) | 402 * 398 = | | 10) 400 * 400 - 2 * 2 = 159996 |
| 11) | 54 * 93 + 46 * 93 = | | 11) ( 54 + 46) * 93 = 9300 |
| 12) | 73 * 70 + 70 * 27 = | | 12) ( 27 + 73) * 70 = 7000 |
| 13) | 170 * 42 - 70 * 42 = | | 13) ( 170 - 70) * 42 = 4200 |
| 14) | 164 * 91 - 64 * 91 = | | 14) ( 164 - 64) * 91 = 9100 |
| 15) | 85 * 171 - 71 * 85 = | | 15) ( 171 - 71) * 85 = 8500 |
| 16) | 88 * 35 + 165 * 88 = | | 16) ( 165 + 35) * 88 = 17600 |
| 17) | 155 * 94 - 55 * 94 = | | 17) ( 155 - 55) * 94 = 9400 |
| 18) | 30 * 251 - 30 * 51 = | | 18) ( 251 - 51) * 30 = 6000 |
| 19) | 47 * 41 + 53 * 41 = | | 19) ( 53 + 47) * 41 = 4100 |
| 20) | 31 * 144 - 44 * 31 = | | 20) ( 144 - 44) * 31 = 3100 |
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Score: ______________ | |
