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 February 25 2026
02:04:42 AM | Wednesday February 25 2026
02:04:42 AMFlip Answers |
| 1) | 391 * 409 = | | 1) 400 * 400 - 9 * 9 = 159919 |
| 2) | 205 * 195 = | | 2) 200 * 200 - 5 * 5 = 39975 |
| 3) | 309 * 291 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 293 * 307 = | | 4) 300 * 300 - 7 * 7 = 89951 |
| 5) | 107 * 93 = | | 5) 100 * 100 - 7 * 7 = 9951 |
| 6) | 394 * 406 = | | 6) 400 * 400 - 6 * 6 = 159964 |
| 7) | 402 * 398 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 295 * 305 = | | 8) 300 * 300 - 5 * 5 = 89975 |
| 9) | 195 * 205 = | | 9) 200 * 200 - 5 * 5 = 39975 |
| 10) | 303 * 297 = | | 10) 300 * 300 - 3 * 3 = 89991 |
| 11) | 48 * 74 + 152 * 74 = | | 11) ( 152 + 48) * 74 = 14800 |
| 12) | 95 * 154 + 46 * 95 = | | 12) ( 154 + 46) * 95 = 19000 |
| 13) | 55 * 56 + 45 * 56 = | | 13) ( 45 + 55) * 56 = 5600 |
| 14) | 71 * 90 + 29 * 90 = | | 14) ( 29 + 71) * 90 = 9000 |
| 15) | 63 * 70 + 30 * 63 = | | 15) ( 30 + 70) * 63 = 6300 |
| 16) | 53 * 65 + 135 * 53 = | | 16) ( 135 + 65) * 53 = 10600 |
| 17) | 62 * 29 + 62 * 71 = | | 17) ( 29 + 71) * 62 = 6200 |
| 18) | 24 * 268 - 68 * 24 = | | 18) ( 268 - 68) * 24 = 4800 |
| 19) | 62 * 153 - 53 * 62 = | | 19) ( 153 - 53) * 62 = 6200 |
| 20) | 52 * 27 + 48 * 27 = | | 20) ( 48 + 52) * 27 = 2700 |
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Score: ______________ | |
