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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Tuesday December 09 2025
11:33:30 AM | Tuesday December 09 2025
11:33:30 AMFlip Answers |
| 1) | 407 * 393 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 301 * 299 = | | 2) 300 * 300 - 1 * 1 = 89999 |
| 3) | 90 * 110 = | | 3) 100 * 100 - 10 * 10 = 9900 |
| 4) | 198 * 202 = | | 4) 200 * 200 - 2 * 2 = 39996 |
| 5) | 207 * 193 = | | 5) 200 * 200 - 7 * 7 = 39951 |
| 6) | 409 * 391 = | | 6) 400 * 400 - 9 * 9 = 159919 |
| 7) | 292 * 308 = | | 7) 300 * 300 - 8 * 8 = 89936 |
| 8) | 409 * 391 = | | 8) 400 * 400 - 9 * 9 = 159919 |
| 9) | 110 * 90 = | | 9) 100 * 100 - 10 * 10 = 9900 |
| 10) | 107 * 93 = | | 10) 100 * 100 - 7 * 7 = 9951 |
| 11) | 95 * 169 - 95 * 69 = | | 11) ( 169 - 69) * 95 = 9500 |
| 12) | 86 * 56 + 44 * 86 = | | 12) ( 44 + 56) * 86 = 8600 |
| 13) | 137 * 30 - 37 * 30 = | | 13) ( 137 - 37) * 30 = 3000 |
| 14) | 79 * 144 + 56 * 79 = | | 14) ( 144 + 56) * 79 = 15800 |
| 15) | 242 * 40 - 42 * 40 = | | 15) ( 242 - 42) * 40 = 8000 |
| 16) | 36 * 71 + 36 * 129 = | | 16) ( 129 + 71) * 36 = 7200 |
| 17) | 83 * 147 - 83 * 47 = | | 17) ( 147 - 47) * 83 = 8300 |
| 18) | 246 * 36 - 46 * 36 = | | 18) ( 246 - 46) * 36 = 7200 |
| 19) | 41 * 270 - 70 * 41 = | | 19) ( 270 - 70) * 41 = 8200 |
| 20) | 65 * 29 + 29 * 135 = | | 20) ( 135 + 65) * 29 = 5800 |
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Score: ______________ | |
