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 July 03 2026
09:46:49 PM | Friday July 03 2026
09:46:49 PMFlip Answers |
| 1) | 109 * 91 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 394 * 406 = | | 2) 400 * 400 - 6 * 6 = 159964 |
| 3) | 406 * 394 = | | 3) 400 * 400 - 6 * 6 = 159964 |
| 4) | 102 * 98 = | | 4) 100 * 100 - 2 * 2 = 9996 |
| 5) | 306 * 294 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 101 * 99 = | | 6) 100 * 100 - 1 * 1 = 9999 |
| 7) | 107 * 93 = | | 7) 100 * 100 - 7 * 7 = 9951 |
| 8) | 399 * 401 = | | 8) 400 * 400 - 1 * 1 = 159999 |
| 9) | 303 * 297 = | | 9) 300 * 300 - 3 * 3 = 89991 |
| 10) | 297 * 303 = | | 10) 300 * 300 - 3 * 3 = 89991 |
| 11) | 52 * 58 + 148 * 58 = | | 11) ( 148 + 52) * 58 = 11600 |
| 12) | 43 * 73 + 127 * 43 = | | 12) ( 127 + 73) * 43 = 8600 |
| 13) | 241 * 76 - 41 * 76 = | | 13) ( 241 - 41) * 76 = 15200 |
| 14) | 149 * 90 - 90 * 49 = | | 14) ( 149 - 49) * 90 = 9000 |
| 15) | 138 * 76 + 76 * 62 = | | 15) ( 138 + 62) * 76 = 15200 |
| 16) | 36 * 155 - 36 * 55 = | | 16) ( 155 - 55) * 36 = 3600 |
| 17) | 53 * 140 - 40 * 53 = | | 17) ( 140 - 40) * 53 = 5300 |
| 18) | 148 * 49 - 49 * 48 = | | 18) ( 148 - 48) * 49 = 4900 |
| 19) | 45 * 26 + 45 * 74 = | | 19) ( 26 + 74) * 45 = 4500 |
| 20) | 249 * 21 - 49 * 21 = | | 20) ( 249 - 49) * 21 = 4200 |
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Score: ______________ | |
