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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Sunday September 06 2026
03:30:03 PM | Sunday September 06 2026
03:30:03 PMFlip Answers |
| 1) | 410 * 390 = | | 1) 400 * 400 - 10 * 10 = 159900 |
| 2) | 303 * 297 = | | 2) 300 * 300 - 3 * 3 = 89991 |
| 3) | 295 * 305 = | | 3) 300 * 300 - 5 * 5 = 89975 |
| 4) | 398 * 402 = | | 4) 400 * 400 - 2 * 2 = 159996 |
| 5) | 303 * 297 = | | 5) 300 * 300 - 3 * 3 = 89991 |
| 6) | 104 * 96 = | | 6) 100 * 100 - 4 * 4 = 9984 |
| 7) | 399 * 401 = | | 7) 400 * 400 - 1 * 1 = 159999 |
| 8) | 306 * 294 = | | 8) 300 * 300 - 6 * 6 = 89964 |
| 9) | 292 * 308 = | | 9) 300 * 300 - 8 * 8 = 89936 |
| 10) | 408 * 392 = | | 10) 400 * 400 - 8 * 8 = 159936 |
| 11) | 41 * 86 + 86 * 59 = | | 11) ( 59 + 41) * 86 = 8600 |
| 12) | 267 * 93 - 93 * 67 = | | 12) ( 267 - 67) * 93 = 18600 |
| 13) | 70 * 265 - 65 * 70 = | | 13) ( 265 - 65) * 70 = 14000 |
| 14) | 38 * 52 + 52 * 62 = | | 14) ( 38 + 62) * 52 = 5200 |
| 15) | 136 * 44 - 44 * 36 = | | 15) ( 136 - 36) * 44 = 4400 |
| 16) | 71 * 76 + 76 * 129 = | | 16) ( 129 + 71) * 76 = 15200 |
| 17) | 23 * 132 + 68 * 23 = | | 17) ( 132 + 68) * 23 = 4600 |
| 18) | 46 * 41 + 54 * 41 = | | 18) ( 46 + 54) * 41 = 4100 |
| 19) | 65 * 33 + 65 * 67 = | | 19) ( 33 + 67) * 65 = 6500 |
| 20) | 67 * 240 - 67 * 40 = | | 20) ( 240 - 40) * 67 = 13400 |
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Score: ______________ | |
