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 August 22 2026
04:32:16 AM | Saturday August 22 2026
04:32:16 AMFlip Answers |
| 1) | 404 * 396 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 208 * 192 = | | 2) 200 * 200 - 8 * 8 = 39936 |
| 3) | 196 * 204 = | | 3) 200 * 200 - 4 * 4 = 39984 |
| 4) | 99 * 101 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 90 * 110 = | | 5) 100 * 100 - 10 * 10 = 9900 |
| 6) | 91 * 109 = | | 6) 100 * 100 - 9 * 9 = 9919 |
| 7) | 409 * 391 = | | 7) 400 * 400 - 9 * 9 = 159919 |
| 8) | 296 * 304 = | | 8) 300 * 300 - 4 * 4 = 89984 |
| 9) | 104 * 96 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 299 * 301 = | | 10) 300 * 300 - 1 * 1 = 89999 |
| 11) | 80 * 40 + 80 * 60 = | | 11) ( 40 + 60) * 80 = 8000 |
| 12) | 43 * 146 - 43 * 46 = | | 12) ( 146 - 46) * 43 = 4300 |
| 13) | 130 * 75 + 70 * 75 = | | 13) ( 130 + 70) * 75 = 15000 |
| 14) | 77 * 35 + 77 * 65 = | | 14) ( 65 + 35) * 77 = 7700 |
| 15) | 55 * 172 - 55 * 72 = | | 15) ( 172 - 72) * 55 = 5500 |
| 16) | 164 * 49 - 49 * 64 = | | 16) ( 164 - 64) * 49 = 4900 |
| 17) | 29 * 249 - 49 * 29 = | | 17) ( 249 - 49) * 29 = 5800 |
| 18) | 63 * 73 + 73 * 37 = | | 18) ( 37 + 63) * 73 = 7300 |
| 19) | 261 * 59 - 59 * 61 = | | 19) ( 261 - 61) * 59 = 11800 |
| 20) | 71 * 81 + 81 * 29 = | | 20) ( 29 + 71) * 81 = 8100 |
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Score: ______________ | |
