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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Friday December 05 2025
02:04:57 AM | Friday December 05 2025
02:04:57 AMFlip Answers |
| 1) | 195 * 205 = | | 1) 200 * 200 - 5 * 5 = 39975 |
| 2) | 191 * 209 = | | 2) 200 * 200 - 9 * 9 = 39919 |
| 3) | 295 * 305 = | | 3) 300 * 300 - 5 * 5 = 89975 |
| 4) | 409 * 391 = | | 4) 400 * 400 - 9 * 9 = 159919 |
| 5) | 92 * 108 = | | 5) 100 * 100 - 8 * 8 = 9936 |
| 6) | 299 * 301 = | | 6) 300 * 300 - 1 * 1 = 89999 |
| 7) | 397 * 403 = | | 7) 400 * 400 - 3 * 3 = 159991 |
| 8) | 408 * 392 = | | 8) 400 * 400 - 8 * 8 = 159936 |
| 9) | 106 * 94 = | | 9) 100 * 100 - 6 * 6 = 9964 |
| 10) | 403 * 397 = | | 10) 400 * 400 - 3 * 3 = 159991 |
| 11) | 41 * 25 + 59 * 25 = | | 11) ( 59 + 41) * 25 = 2500 |
| 12) | 45 * 150 + 45 * 50 = | | 12) ( 150 + 50) * 45 = 9000 |
| 13) | 80 * 256 - 80 * 56 = | | 13) ( 256 - 56) * 80 = 16000 |
| 14) | 64 * 61 + 61 * 36 = | | 14) ( 64 + 36) * 61 = 6100 |
| 15) | 60 * 82 + 82 * 140 = | | 15) ( 140 + 60) * 82 = 16400 |
| 16) | 92 * 72 + 128 * 92 = | | 16) ( 128 + 72) * 92 = 18400 |
| 17) | 64 * 238 - 64 * 38 = | | 17) ( 238 - 38) * 64 = 12800 |
| 18) | 27 * 150 + 27 * 50 = | | 18) ( 150 + 50) * 27 = 5400 |
| 19) | 236 * 55 - 36 * 55 = | | 19) ( 236 - 36) * 55 = 11000 |
| 20) | 31 * 163 - 63 * 31 = | | 20) ( 163 - 63) * 31 = 3100 |
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Score: ______________ | |
