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 20 2026
07:07:00 AM | Tuesday January 20 2026
07:07:00 AMFlip Answers |
| 1) | 396 * 404 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 399 * 401 = | | 2) 400 * 400 - 1 * 1 = 159999 |
| 3) | 191 * 209 = | | 3) 200 * 200 - 9 * 9 = 39919 |
| 4) | 301 * 299 = | | 4) 300 * 300 - 1 * 1 = 89999 |
| 5) | 306 * 294 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 91 * 109 = | | 6) 100 * 100 - 9 * 9 = 9919 |
| 7) | 392 * 408 = | | 7) 400 * 400 - 8 * 8 = 159936 |
| 8) | 403 * 397 = | | 8) 400 * 400 - 3 * 3 = 159991 |
| 9) | 205 * 195 = | | 9) 200 * 200 - 5 * 5 = 39975 |
| 10) | 194 * 206 = | | 10) 200 * 200 - 6 * 6 = 39964 |
| 11) | 271 * 67 - 67 * 71 = | | 11) ( 271 - 71) * 67 = 13400 |
| 12) | 52 * 46 + 148 * 46 = | | 12) ( 148 + 52) * 46 = 9200 |
| 13) | 245 * 52 - 52 * 45 = | | 13) ( 245 - 45) * 52 = 10400 |
| 14) | 64 * 81 + 36 * 81 = | | 14) ( 36 + 64) * 81 = 8100 |
| 15) | 93 * 152 - 52 * 93 = | | 15) ( 152 - 52) * 93 = 9300 |
| 16) | 44 * 275 - 44 * 75 = | | 16) ( 275 - 75) * 44 = 8800 |
| 17) | 260 * 44 - 60 * 44 = | | 17) ( 260 - 60) * 44 = 8800 |
| 18) | 248 * 60 - 48 * 60 = | | 18) ( 248 - 48) * 60 = 12000 |
| 19) | 72 * 47 + 47 * 128 = | | 19) ( 128 + 72) * 47 = 9400 |
| 20) | 67 * 81 + 133 * 81 = | | 20) ( 133 + 67) * 81 = 16200 |
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Score: ______________ | |
