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 August 07 2026
11:47:55 AM | Friday August 07 2026
11:47:55 AMFlip Answers |
| 1) | 405 * 395 = | | 1) 400 * 400 - 5 * 5 = 159975 |
| 2) | 204 * 196 = | | 2) 200 * 200 - 4 * 4 = 39984 |
| 3) | 92 * 108 = | | 3) 100 * 100 - 8 * 8 = 9936 |
| 4) | 208 * 192 = | | 4) 200 * 200 - 8 * 8 = 39936 |
| 5) | 90 * 110 = | | 5) 100 * 100 - 10 * 10 = 9900 |
| 6) | 310 * 290 = | | 6) 300 * 300 - 10 * 10 = 89900 |
| 7) | 290 * 310 = | | 7) 300 * 300 - 10 * 10 = 89900 |
| 8) | 396 * 404 = | | 8) 400 * 400 - 4 * 4 = 159984 |
| 9) | 105 * 95 = | | 9) 100 * 100 - 5 * 5 = 9975 |
| 10) | 106 * 94 = | | 10) 100 * 100 - 6 * 6 = 9964 |
| 11) | 34 * 41 + 41 * 66 = | | 11) ( 34 + 66) * 41 = 4100 |
| 12) | 57 * 130 + 57 * 70 = | | 12) ( 130 + 70) * 57 = 11400 |
| 13) | 55 * 75 + 145 * 75 = | | 13) ( 145 + 55) * 75 = 15000 |
| 14) | 85 * 172 - 85 * 72 = | | 14) ( 172 - 72) * 85 = 8500 |
| 15) | 154 * 92 - 92 * 54 = | | 15) ( 154 - 54) * 92 = 9200 |
| 16) | 63 * 31 + 137 * 31 = | | 16) ( 137 + 63) * 31 = 6200 |
| 17) | 23 * 44 + 23 * 56 = | | 17) ( 56 + 44) * 23 = 2300 |
| 18) | 272 * 37 - 37 * 72 = | | 18) ( 272 - 72) * 37 = 7400 |
| 19) | 49 * 34 + 49 * 66 = | | 19) ( 34 + 66) * 49 = 4900 |
| 20) | 160 * 36 - 60 * 36 = | | 20) ( 160 - 60) * 36 = 3600 |
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Score: ______________ | |
