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 December 31 2025
10:59:36 AM | Wednesday December 31 2025
10:59:36 AMFlip Answers |
| 1) | 407 * 393 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 204 * 196 = | | 2) 200 * 200 - 4 * 4 = 39984 |
| 3) | 107 * 93 = | | 3) 100 * 100 - 7 * 7 = 9951 |
| 4) | 197 * 203 = | | 4) 200 * 200 - 3 * 3 = 39991 |
| 5) | 396 * 404 = | | 5) 400 * 400 - 4 * 4 = 159984 |
| 6) | 207 * 193 = | | 6) 200 * 200 - 7 * 7 = 39951 |
| 7) | 406 * 394 = | | 7) 400 * 400 - 6 * 6 = 159964 |
| 8) | 110 * 90 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 206 * 194 = | | 9) 200 * 200 - 6 * 6 = 39964 |
| 10) | 308 * 292 = | | 10) 300 * 300 - 8 * 8 = 89936 |
| 11) | 255 * 64 - 55 * 64 = | | 11) ( 255 - 55) * 64 = 12800 |
| 12) | 149 * 54 + 54 * 51 = | | 12) ( 149 + 51) * 54 = 10800 |
| 13) | 255 * 29 - 55 * 29 = | | 13) ( 255 - 55) * 29 = 5800 |
| 14) | 136 * 95 - 95 * 36 = | | 14) ( 136 - 36) * 95 = 9500 |
| 15) | 139 * 38 + 38 * 61 = | | 15) ( 139 + 61) * 38 = 7600 |
| 16) | 42 * 170 - 42 * 70 = | | 16) ( 170 - 70) * 42 = 4200 |
| 17) | 64 * 62 + 136 * 62 = | | 17) ( 136 + 64) * 62 = 12400 |
| 18) | 41 * 83 + 83 * 59 = | | 18) ( 41 + 59) * 83 = 8300 |
| 19) | 168 * 57 - 68 * 57 = | | 19) ( 168 - 68) * 57 = 5700 |
| 20) | 27 * 135 - 27 * 35 = | | 20) ( 135 - 35) * 27 = 2700 |
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Score: ______________ | |
