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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Wednesday February 11 2026 02:48:40 PM | Wednesday February 11 2026 02:48:40 PMFlip Answers |
| 1) | 192 * 208 = | | 1) 200 * 200 - 8 * 8 = 39936 |
| 2) | 93 * 107 = | | 2) 100 * 100 - 7 * 7 = 9951 |
| 3) | 109 * 91 = | | 3) 100 * 100 - 9 * 9 = 9919 |
| 4) | 301 * 299 = | | 4) 300 * 300 - 1 * 1 = 89999 |
| 5) | 203 * 197 = | | 5) 200 * 200 - 3 * 3 = 39991 |
| 6) | 209 * 191 = | | 6) 200 * 200 - 9 * 9 = 39919 |
| 7) | 196 * 204 = | | 7) 200 * 200 - 4 * 4 = 39984 |
| 8) | 410 * 390 = | | 8) 400 * 400 - 10 * 10 = 159900 |
| 9) | 391 * 409 = | | 9) 400 * 400 - 9 * 9 = 159919 |
| 10) | 94 * 106 = | | 10) 100 * 100 - 6 * 6 = 9964 |
| 11) | 151 * 87 + 49 * 87 = | | 11) ( 151 + 49) * 87 = 17400 |
| 12) | 49 * 271 - 71 * 49 = | | 12) ( 271 - 71) * 49 = 9800 |
| 13) | 40 * 163 - 63 * 40 = | | 13) ( 163 - 63) * 40 = 4000 |
| 14) | 51 * 235 - 51 * 35 = | | 14) ( 235 - 35) * 51 = 10200 |
| 15) | 163 * 89 + 37 * 89 = | | 15) ( 163 + 37) * 89 = 17800 |
| 16) | 28 * 45 + 55 * 28 = | | 16) ( 55 + 45) * 28 = 2800 |
| 17) | 55 * 38 + 162 * 55 = | | 17) ( 162 + 38) * 55 = 11000 |
| 18) | 44 * 157 + 43 * 44 = | | 18) ( 157 + 43) * 44 = 8800 |
| 19) | 76 * 61 + 39 * 76 = | | 19) ( 61 + 39) * 76 = 7600 |
| 20) | 271 * 33 - 33 * 71 = | | 20) ( 271 - 71) * 33 = 6600 |
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Score: ______________ | |