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 August 05 2026
10:39:11 AM | Wednesday August 05 2026
10:39:11 AMFlip Answers |
| 1) | 402 * 398 = | | 1) 400 * 400 - 2 * 2 = 159996 |
| 2) | 406 * 394 = | | 2) 400 * 400 - 6 * 6 = 159964 |
| 3) | 91 * 109 = | | 3) 100 * 100 - 9 * 9 = 9919 |
| 4) | 409 * 391 = | | 4) 400 * 400 - 9 * 9 = 159919 |
| 5) | 306 * 294 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 295 * 305 = | | 6) 300 * 300 - 5 * 5 = 89975 |
| 7) | 294 * 306 = | | 7) 300 * 300 - 6 * 6 = 89964 |
| 8) | 97 * 103 = | | 8) 100 * 100 - 3 * 3 = 9991 |
| 9) | 109 * 91 = | | 9) 100 * 100 - 9 * 9 = 9919 |
| 10) | 108 * 92 = | | 10) 100 * 100 - 8 * 8 = 9936 |
| 11) | 42 * 50 + 42 * 50 = | | 11) ( 50 + 50) * 42 = 4200 |
| 12) | 274 * 95 - 95 * 74 = | | 12) ( 274 - 74) * 95 = 19000 |
| 13) | 74 * 167 - 74 * 67 = | | 13) ( 167 - 67) * 74 = 7400 |
| 14) | 59 * 136 - 59 * 36 = | | 14) ( 136 - 36) * 59 = 5900 |
| 15) | 54 * 153 - 53 * 54 = | | 15) ( 153 - 53) * 54 = 5400 |
| 16) | 80 * 152 - 52 * 80 = | | 16) ( 152 - 52) * 80 = 8000 |
| 17) | 136 * 97 - 97 * 36 = | | 17) ( 136 - 36) * 97 = 9700 |
| 18) | 62 * 38 + 38 * 38 = | | 18) ( 62 + 38) * 38 = 3800 |
| 19) | 159 * 67 - 67 * 59 = | | 19) ( 159 - 59) * 67 = 6700 |
| 20) | 25 * 63 + 25 * 137 = | | 20) ( 137 + 63) * 25 = 5000 |
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Score: ______________ | |
