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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Tuesday January 27 2026 05:18:16 AM | Tuesday January 27 2026 05:18:16 AMFlip Answers |
| 1) | 107 * 93 = | | 1) 100 * 100 - 7 * 7 = 9951 |
| 2) | 305 * 295 = | | 2) 300 * 300 - 5 * 5 = 89975 |
| 3) | 191 * 209 = | | 3) 200 * 200 - 9 * 9 = 39919 |
| 4) | 301 * 299 = | | 4) 300 * 300 - 1 * 1 = 89999 |
| 5) | 106 * 94 = | | 5) 100 * 100 - 6 * 6 = 9964 |
| 6) | 408 * 392 = | | 6) 400 * 400 - 8 * 8 = 159936 |
| 7) | 404 * 396 = | | 7) 400 * 400 - 4 * 4 = 159984 |
| 8) | 291 * 309 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 305 * 295 = | | 9) 300 * 300 - 5 * 5 = 89975 |
| 10) | 306 * 294 = | | 10) 300 * 300 - 6 * 6 = 89964 |
| 11) | 171 * 22 - 71 * 22 = | | 11) ( 171 - 71) * 22 = 2200 |
| 12) | 40 * 242 - 42 * 40 = | | 12) ( 242 - 42) * 40 = 8000 |
| 13) | 28 * 148 - 28 * 48 = | | 13) ( 148 - 48) * 28 = 2800 |
| 14) | 87 * 256 - 56 * 87 = | | 14) ( 256 - 56) * 87 = 17400 |
| 15) | 40 * 242 - 42 * 40 = | | 15) ( 242 - 42) * 40 = 8000 |
| 16) | 30 * 251 - 30 * 51 = | | 16) ( 251 - 51) * 30 = 6000 |
| 17) | 265 * 33 - 65 * 33 = | | 17) ( 265 - 65) * 33 = 6600 |
| 18) | 51 * 250 - 51 * 50 = | | 18) ( 250 - 50) * 51 = 10200 |
| 19) | 261 * 33 - 33 * 61 = | | 19) ( 261 - 61) * 33 = 6600 |
| 20) | 80 * 64 + 80 * 36 = | | 20) ( 36 + 64) * 80 = 8000 |
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Score: ______________ | |