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 December 14 2025
07:15:59 AM | Sunday December 14 2025
07:15:59 AMFlip Answers |
| 1) | 105 * 95 = | | 1) 100 * 100 - 5 * 5 = 9975 |
| 2) | 290 * 310 = | | 2) 300 * 300 - 10 * 10 = 89900 |
| 3) | 90 * 110 = | | 3) 100 * 100 - 10 * 10 = 9900 |
| 4) | 204 * 196 = | | 4) 200 * 200 - 4 * 4 = 39984 |
| 5) | 102 * 98 = | | 5) 100 * 100 - 2 * 2 = 9996 |
| 6) | 96 * 104 = | | 6) 100 * 100 - 4 * 4 = 9984 |
| 7) | 398 * 402 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 191 * 209 = | | 8) 200 * 200 - 9 * 9 = 39919 |
| 9) | 94 * 106 = | | 9) 100 * 100 - 6 * 6 = 9964 |
| 10) | 295 * 305 = | | 10) 300 * 300 - 5 * 5 = 89975 |
| 11) | 72 * 241 - 41 * 72 = | | 11) ( 241 - 41) * 72 = 14400 |
| 12) | 77 * 168 - 68 * 77 = | | 12) ( 168 - 68) * 77 = 7700 |
| 13) | 38 * 31 + 31 * 162 = | | 13) ( 162 + 38) * 31 = 6200 |
| 14) | 40 * 69 + 60 * 69 = | | 14) ( 60 + 40) * 69 = 6900 |
| 15) | 68 * 129 + 71 * 68 = | | 15) ( 129 + 71) * 68 = 13600 |
| 16) | 39 * 155 + 45 * 39 = | | 16) ( 155 + 45) * 39 = 7800 |
| 17) | 48 * 258 - 58 * 48 = | | 17) ( 258 - 58) * 48 = 9600 |
| 18) | 267 * 86 - 67 * 86 = | | 18) ( 267 - 67) * 86 = 17200 |
| 19) | 66 * 34 + 34 * 34 = | | 19) ( 34 + 66) * 34 = 3400 |
| 20) | 255 * 38 - 38 * 55 = | | 20) ( 255 - 55) * 38 = 7600 |
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Score: ______________ | |
