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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Saturday May 16 2026
07:42:32 PM | Saturday May 16 2026
07:42:32 PMFlip Answers |
| 1) | 192 * 208 = | | 1) 200 * 200 - 8 * 8 = 39936 |
| 2) | 304 * 296 = | | 2) 300 * 300 - 4 * 4 = 89984 |
| 3) | 296 * 304 = | | 3) 300 * 300 - 4 * 4 = 89984 |
| 4) | 403 * 397 = | | 4) 400 * 400 - 3 * 3 = 159991 |
| 5) | 406 * 394 = | | 5) 400 * 400 - 6 * 6 = 159964 |
| 6) | 409 * 391 = | | 6) 400 * 400 - 9 * 9 = 159919 |
| 7) | 204 * 196 = | | 7) 200 * 200 - 4 * 4 = 39984 |
| 8) | 309 * 291 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 110 * 90 = | | 9) 100 * 100 - 10 * 10 = 9900 |
| 10) | 298 * 302 = | | 10) 300 * 300 - 2 * 2 = 89996 |
| 11) | 30 * 175 - 75 * 30 = | | 11) ( 175 - 75) * 30 = 3000 |
| 12) | 50 * 51 + 51 * 50 = | | 12) ( 50 + 50) * 51 = 5100 |
| 13) | 76 * 149 - 49 * 76 = | | 13) ( 149 - 49) * 76 = 7600 |
| 14) | 58 * 77 + 77 * 42 = | | 14) ( 58 + 42) * 77 = 7700 |
| 15) | 65 * 35 + 165 * 65 = | | 15) ( 165 + 35) * 65 = 13000 |
| 16) | 82 * 75 + 125 * 82 = | | 16) ( 125 + 75) * 82 = 16400 |
| 17) | 80 * 130 + 70 * 80 = | | 17) ( 130 + 70) * 80 = 16000 |
| 18) | 43 * 163 - 63 * 43 = | | 18) ( 163 - 63) * 43 = 4300 |
| 19) | 157 * 37 - 57 * 37 = | | 19) ( 157 - 57) * 37 = 3700 |
| 20) | 55 * 31 + 31 * 145 = | | 20) ( 145 + 55) * 31 = 6200 |
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Score: ______________ | |
