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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Wednesday September 30 2026
06:18:14 AM | Wednesday September 30 2026
06:18:14 AMFlip Answers |
| 1) | 408 * 392 = | | 1) 400 * 400 - 8 * 8 = 159936 |
| 2) | 396 * 404 = | | 2) 400 * 400 - 4 * 4 = 159984 |
| 3) | 409 * 391 = | | 3) 400 * 400 - 9 * 9 = 159919 |
| 4) | 302 * 298 = | | 4) 300 * 300 - 2 * 2 = 89996 |
| 5) | 390 * 410 = | | 5) 400 * 400 - 10 * 10 = 159900 |
| 6) | 304 * 296 = | | 6) 300 * 300 - 4 * 4 = 89984 |
| 7) | 402 * 398 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 298 * 302 = | | 8) 300 * 300 - 2 * 2 = 89996 |
| 9) | 394 * 406 = | | 9) 400 * 400 - 6 * 6 = 159964 |
| 10) | 392 * 408 = | | 10) 400 * 400 - 8 * 8 = 159936 |
| 11) | 73 * 49 + 151 * 73 = | | 11) ( 151 + 49) * 73 = 14600 |
| 12) | 149 * 46 - 49 * 46 = | | 12) ( 149 - 49) * 46 = 4600 |
| 13) | 162 * 55 - 62 * 55 = | | 13) ( 162 - 62) * 55 = 5500 |
| 14) | 136 * 74 - 74 * 36 = | | 14) ( 136 - 36) * 74 = 7400 |
| 15) | 161 * 30 - 61 * 30 = | | 15) ( 161 - 61) * 30 = 3000 |
| 16) | 70 * 68 + 130 * 68 = | | 16) ( 130 + 70) * 68 = 13600 |
| 17) | 68 * 70 + 32 * 70 = | | 17) ( 32 + 68) * 70 = 7000 |
| 18) | 97 * 48 + 97 * 52 = | | 18) ( 48 + 52) * 97 = 9700 |
| 19) | 30 * 242 - 30 * 42 = | | 19) ( 242 - 42) * 30 = 6000 |
| 20) | 92 * 149 - 49 * 92 = | | 20) ( 149 - 49) * 92 = 9200 |
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Score: ______________ | |
