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 April 14 2026
07:44:51 AM | Tuesday April 14 2026
07:44:51 AMFlip Answers |
| 1) | 403 * 397 = | | 1) 400 * 400 - 3 * 3 = 159991 |
| 2) | 410 * 390 = | | 2) 400 * 400 - 10 * 10 = 159900 |
| 3) | 291 * 309 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 298 * 302 = | | 4) 300 * 300 - 2 * 2 = 89996 |
| 5) | 192 * 208 = | | 5) 200 * 200 - 8 * 8 = 39936 |
| 6) | 296 * 304 = | | 6) 300 * 300 - 4 * 4 = 89984 |
| 7) | 402 * 398 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 390 * 410 = | | 8) 400 * 400 - 10 * 10 = 159900 |
| 9) | 404 * 396 = | | 9) 400 * 400 - 4 * 4 = 159984 |
| 10) | 298 * 302 = | | 10) 300 * 300 - 2 * 2 = 89996 |
| 11) | 92 * 45 + 55 * 92 = | | 11) ( 45 + 55) * 92 = 9200 |
| 12) | 57 * 70 + 70 * 43 = | | 12) ( 57 + 43) * 70 = 7000 |
| 13) | 146 * 68 - 46 * 68 = | | 13) ( 146 - 46) * 68 = 6800 |
| 14) | 173 * 58 - 73 * 58 = | | 14) ( 173 - 73) * 58 = 5800 |
| 15) | 27 * 137 - 37 * 27 = | | 15) ( 137 - 37) * 27 = 2700 |
| 16) | 273 * 32 - 73 * 32 = | | 16) ( 273 - 73) * 32 = 6400 |
| 17) | 25 * 25 + 25 * 75 = | | 17) ( 25 + 75) * 25 = 2500 |
| 18) | 63 * 78 + 78 * 37 = | | 18) ( 63 + 37) * 78 = 7800 |
| 19) | 34 * 54 + 46 * 34 = | | 19) ( 46 + 54) * 34 = 3400 |
| 20) | 27 * 31 + 73 * 31 = | | 20) ( 27 + 73) * 31 = 3100 |
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Score: ______________ | |
