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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Saturday October 10 2026
04:08:04 PM | Saturday October 10 2026
04:08:04 PMFlip Answers |
| 1) | 303 * 297 = | | 1) 300 * 300 - 3 * 3 = 89991 |
| 2) | 392 * 408 = | | 2) 400 * 400 - 8 * 8 = 159936 |
| 3) | 392 * 408 = | | 3) 400 * 400 - 8 * 8 = 159936 |
| 4) | 402 * 398 = | | 4) 400 * 400 - 2 * 2 = 159996 |
| 5) | 110 * 90 = | | 5) 100 * 100 - 10 * 10 = 9900 |
| 6) | 399 * 401 = | | 6) 400 * 400 - 1 * 1 = 159999 |
| 7) | 95 * 105 = | | 7) 100 * 100 - 5 * 5 = 9975 |
| 8) | 304 * 296 = | | 8) 300 * 300 - 4 * 4 = 89984 |
| 9) | 399 * 401 = | | 9) 400 * 400 - 1 * 1 = 159999 |
| 10) | 402 * 398 = | | 10) 400 * 400 - 2 * 2 = 159996 |
| 11) | 41 * 46 + 46 * 59 = | | 11) ( 59 + 41) * 46 = 4600 |
| 12) | 130 * 90 + 70 * 90 = | | 12) ( 130 + 70) * 90 = 18000 |
| 13) | 73 * 55 + 27 * 55 = | | 13) ( 27 + 73) * 55 = 5500 |
| 14) | 160 * 22 + 22 * 40 = | | 14) ( 160 + 40) * 22 = 4400 |
| 15) | 62 * 47 + 53 * 62 = | | 15) ( 47 + 53) * 62 = 6200 |
| 16) | 68 * 55 + 45 * 68 = | | 16) ( 55 + 45) * 68 = 6800 |
| 17) | 42 * 68 + 68 * 58 = | | 17) ( 58 + 42) * 68 = 6800 |
| 18) | 70 * 45 + 155 * 70 = | | 18) ( 155 + 45) * 70 = 14000 |
| 19) | 87 * 52 + 48 * 87 = | | 19) ( 52 + 48) * 87 = 8700 |
| 20) | 47 * 73 + 27 * 47 = | | 20) ( 27 + 73) * 47 = 4700 |
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Score: ______________ | |
