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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Thursday September 10 2026
07:48:22 PM | Thursday September 10 2026
07:48:22 PMFlip Answers |
| 1) | 90 * 110 = | | 1) 100 * 100 - 10 * 10 = 9900 |
| 2) | 208 * 192 = | | 2) 200 * 200 - 8 * 8 = 39936 |
| 3) | 399 * 401 = | | 3) 400 * 400 - 1 * 1 = 159999 |
| 4) | 305 * 295 = | | 4) 300 * 300 - 5 * 5 = 89975 |
| 5) | 194 * 206 = | | 5) 200 * 200 - 6 * 6 = 39964 |
| 6) | 204 * 196 = | | 6) 200 * 200 - 4 * 4 = 39984 |
| 7) | 407 * 393 = | | 7) 400 * 400 - 7 * 7 = 159951 |
| 8) | 106 * 94 = | | 8) 100 * 100 - 6 * 6 = 9964 |
| 9) | 398 * 402 = | | 9) 400 * 400 - 2 * 2 = 159996 |
| 10) | 209 * 191 = | | 10) 200 * 200 - 9 * 9 = 39919 |
| 11) | 175 * 85 - 75 * 85 = | | 11) ( 175 - 75) * 85 = 8500 |
| 12) | 32 * 272 - 32 * 72 = | | 12) ( 272 - 72) * 32 = 6400 |
| 13) | 84 * 271 - 71 * 84 = | | 13) ( 271 - 71) * 84 = 16800 |
| 14) | 58 * 37 + 42 * 37 = | | 14) ( 42 + 58) * 37 = 3700 |
| 15) | 65 * 168 - 65 * 68 = | | 15) ( 168 - 68) * 65 = 6500 |
| 16) | 135 * 48 - 35 * 48 = | | 16) ( 135 - 35) * 48 = 4800 |
| 17) | 88 * 173 - 88 * 73 = | | 17) ( 173 - 73) * 88 = 8800 |
| 18) | 54 * 263 - 63 * 54 = | | 18) ( 263 - 63) * 54 = 10800 |
| 19) | 51 * 32 + 32 * 49 = | | 19) ( 51 + 49) * 32 = 3200 |
| 20) | 43 * 84 + 84 * 57 = | | 20) ( 43 + 57) * 84 = 8400 |
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Score: ______________ | |
