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 September 11 2026
07:58:25 PM | Friday September 11 2026
07:58:25 PMFlip Answers |
| 1) | 396 * 404 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 401 * 399 = | | 2) 400 * 400 - 1 * 1 = 159999 |
| 3) | 104 * 96 = | | 3) 100 * 100 - 4 * 4 = 9984 |
| 4) | 208 * 192 = | | 4) 200 * 200 - 8 * 8 = 39936 |
| 5) | 395 * 405 = | | 5) 400 * 400 - 5 * 5 = 159975 |
| 6) | 405 * 395 = | | 6) 400 * 400 - 5 * 5 = 159975 |
| 7) | 409 * 391 = | | 7) 400 * 400 - 9 * 9 = 159919 |
| 8) | 307 * 293 = | | 8) 300 * 300 - 7 * 7 = 89951 |
| 9) | 396 * 404 = | | 9) 400 * 400 - 4 * 4 = 159984 |
| 10) | 301 * 299 = | | 10) 300 * 300 - 1 * 1 = 89999 |
| 11) | 67 * 38 + 33 * 38 = | | 11) ( 33 + 67) * 38 = 3800 |
| 12) | 33 * 47 + 67 * 47 = | | 12) ( 33 + 67) * 47 = 4700 |
| 13) | 63 * 135 - 35 * 63 = | | 13) ( 135 - 35) * 63 = 6300 |
| 14) | 71 * 43 + 43 * 129 = | | 14) ( 129 + 71) * 43 = 8600 |
| 15) | 92 * 133 + 67 * 92 = | | 15) ( 133 + 67) * 92 = 18400 |
| 16) | 153 * 48 - 48 * 53 = | | 16) ( 153 - 53) * 48 = 4800 |
| 17) | 153 * 45 + 45 * 47 = | | 17) ( 153 + 47) * 45 = 9000 |
| 18) | 69 * 64 + 64 * 31 = | | 18) ( 31 + 69) * 64 = 6400 |
| 19) | 53 * 251 - 51 * 53 = | | 19) ( 251 - 51) * 53 = 10600 |
| 20) | 58 * 24 + 24 * 142 = | | 20) ( 142 + 58) * 24 = 4800 |
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Score: ______________ | |
