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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Sunday May 17 2026
10:10:01 AM | Sunday May 17 2026
10:10:01 AMFlip Answers |
| 1) | 205 * 195 = | | 1) 200 * 200 - 5 * 5 = 39975 |
| 2) | 104 * 96 = | | 2) 100 * 100 - 4 * 4 = 9984 |
| 3) | 201 * 199 = | | 3) 200 * 200 - 1 * 1 = 39999 |
| 4) | 194 * 206 = | | 4) 200 * 200 - 6 * 6 = 39964 |
| 5) | 396 * 404 = | | 5) 400 * 400 - 4 * 4 = 159984 |
| 6) | 303 * 297 = | | 6) 300 * 300 - 3 * 3 = 89991 |
| 7) | 305 * 295 = | | 7) 300 * 300 - 5 * 5 = 89975 |
| 8) | 109 * 91 = | | 8) 100 * 100 - 9 * 9 = 9919 |
| 9) | 302 * 298 = | | 9) 300 * 300 - 2 * 2 = 89996 |
| 10) | 407 * 393 = | | 10) 400 * 400 - 7 * 7 = 159951 |
| 11) | 154 * 31 + 31 * 46 = | | 11) ( 154 + 46) * 31 = 6200 |
| 12) | 143 * 34 - 34 * 43 = | | 12) ( 143 - 43) * 34 = 3400 |
| 13) | 44 * 58 + 56 * 58 = | | 13) ( 44 + 56) * 58 = 5800 |
| 14) | 91 * 58 + 142 * 91 = | | 14) ( 142 + 58) * 91 = 18200 |
| 15) | 50 * 79 + 79 * 50 = | | 15) ( 50 + 50) * 79 = 7900 |
| 16) | 80 * 264 - 80 * 64 = | | 16) ( 264 - 64) * 80 = 16000 |
| 17) | 82 * 60 + 82 * 40 = | | 17) ( 40 + 60) * 82 = 8200 |
| 18) | 246 * 94 - 94 * 46 = | | 18) ( 246 - 46) * 94 = 18800 |
| 19) | 140 * 51 - 51 * 40 = | | 19) ( 140 - 40) * 51 = 5100 |
| 20) | 50 * 36 + 64 * 50 = | | 20) ( 36 + 64) * 50 = 5000 |
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Score: ______________ | |
