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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Monday April 20 2026
08:08:45 AM | Monday April 20 2026
08:08:45 AMFlip Answers |
| 1) | 301 * 299 = | | 1) 300 * 300 - 1 * 1 = 89999 |
| 2) | 392 * 408 = | | 2) 400 * 400 - 8 * 8 = 159936 |
| 3) | 410 * 390 = | | 3) 400 * 400 - 10 * 10 = 159900 |
| 4) | 106 * 94 = | | 4) 100 * 100 - 6 * 6 = 9964 |
| 5) | 103 * 97 = | | 5) 100 * 100 - 3 * 3 = 9991 |
| 6) | 396 * 404 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 391 * 409 = | | 7) 400 * 400 - 9 * 9 = 159919 |
| 8) | 406 * 394 = | | 8) 400 * 400 - 6 * 6 = 159964 |
| 9) | 309 * 291 = | | 9) 300 * 300 - 9 * 9 = 89919 |
| 10) | 306 * 294 = | | 10) 300 * 300 - 6 * 6 = 89964 |
| 11) | 38 * 153 - 53 * 38 = | | 11) ( 153 - 53) * 38 = 3800 |
| 12) | 85 * 50 + 150 * 85 = | | 12) ( 150 + 50) * 85 = 17000 |
| 13) | 79 * 151 + 49 * 79 = | | 13) ( 151 + 49) * 79 = 15800 |
| 14) | 61 * 43 + 39 * 43 = | | 14) ( 39 + 61) * 43 = 4300 |
| 15) | 55 * 139 - 55 * 39 = | | 15) ( 139 - 39) * 55 = 5500 |
| 16) | 74 * 36 + 36 * 126 = | | 16) ( 126 + 74) * 36 = 7200 |
| 17) | 60 * 40 + 40 * 40 = | | 17) ( 40 + 60) * 40 = 4000 |
| 18) | 153 * 61 + 47 * 61 = | | 18) ( 153 + 47) * 61 = 12200 |
| 19) | 53 * 39 + 53 * 61 = | | 19) ( 39 + 61) * 53 = 5300 |
| 20) | 239 * 93 - 93 * 39 = | | 20) ( 239 - 39) * 93 = 18600 |
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Score: ______________ | |
