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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Thursday March 12 2026 07:34:55 AM | Thursday March 12 2026 07:34:55 AMFlip Answers |
| 1) | 290 * 310 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 292 * 308 = | | 2) 300 * 300 - 8 * 8 = 89936 |
| 3) | 304 * 296 = | | 3) 300 * 300 - 4 * 4 = 89984 |
| 4) | 307 * 293 = | | 4) 300 * 300 - 7 * 7 = 89951 |
| 5) | 294 * 306 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 104 * 96 = | | 6) 100 * 100 - 4 * 4 = 9984 |
| 7) | 408 * 392 = | | 7) 400 * 400 - 8 * 8 = 159936 |
| 8) | 191 * 209 = | | 8) 200 * 200 - 9 * 9 = 39919 |
| 9) | 210 * 190 = | | 9) 200 * 200 - 10 * 10 = 39900 |
| 10) | 99 * 101 = | | 10) 100 * 100 - 1 * 1 = 9999 |
| 11) | 87 * 146 + 87 * 54 = | | 11) ( 146 + 54) * 87 = 17400 |
| 12) | 263 * 52 - 63 * 52 = | | 12) ( 263 - 63) * 52 = 10400 |
| 13) | 69 * 148 - 69 * 48 = | | 13) ( 148 - 48) * 69 = 6900 |
| 14) | 30 * 245 - 30 * 45 = | | 14) ( 245 - 45) * 30 = 6000 |
| 15) | 255 * 66 - 66 * 55 = | | 15) ( 255 - 55) * 66 = 13200 |
| 16) | 64 * 261 - 64 * 61 = | | 16) ( 261 - 61) * 64 = 12800 |
| 17) | 44 * 154 + 46 * 44 = | | 17) ( 154 + 46) * 44 = 8800 |
| 18) | 55 * 59 + 41 * 55 = | | 18) ( 59 + 41) * 55 = 5500 |
| 19) | 246 * 86 - 86 * 46 = | | 19) ( 246 - 46) * 86 = 17200 |
| 20) | 42 * 162 - 42 * 62 = | | 20) ( 162 - 62) * 42 = 4200 |
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Score: ______________ | |