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 May 22 2026 07:03:18 AM | Friday May 22 2026 07:03:18 AMFlip Answers |
| 1) | 404 * 396 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 104 * 96 = | | 2) 100 * 100 - 4 * 4 = 9984 |
| 3) | 394 * 406 = | | 3) 400 * 400 - 6 * 6 = 159964 |
| 4) | 92 * 108 = | | 4) 100 * 100 - 8 * 8 = 9936 |
| 5) | 109 * 91 = | | 5) 100 * 100 - 9 * 9 = 9919 |
| 6) | 206 * 194 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 107 * 93 = | | 7) 100 * 100 - 7 * 7 = 9951 |
| 8) | 104 * 96 = | | 8) 100 * 100 - 4 * 4 = 9984 |
| 9) | 101 * 99 = | | 9) 100 * 100 - 1 * 1 = 9999 |
| 10) | 95 * 105 = | | 10) 100 * 100 - 5 * 5 = 9975 |
| 11) | 83 * 148 + 52 * 83 = | | 11) ( 148 + 52) * 83 = 16600 |
| 12) | 268 * 58 - 58 * 68 = | | 12) ( 268 - 68) * 58 = 11600 |
| 13) | 90 * 158 - 90 * 58 = | | 13) ( 158 - 58) * 90 = 9000 |
| 14) | 134 * 92 + 92 * 66 = | | 14) ( 134 + 66) * 92 = 18400 |
| 15) | 72 * 168 - 72 * 68 = | | 15) ( 168 - 68) * 72 = 7200 |
| 16) | 270 * 40 - 70 * 40 = | | 16) ( 270 - 70) * 40 = 8000 |
| 17) | 257 * 51 - 57 * 51 = | | 17) ( 257 - 57) * 51 = 10200 |
| 18) | 140 * 76 - 40 * 76 = | | 18) ( 140 - 40) * 76 = 7600 |
| 19) | 60 * 254 - 60 * 54 = | | 19) ( 254 - 54) * 60 = 12000 |
| 20) | 144 * 87 + 56 * 87 = | | 20) ( 144 + 56) * 87 = 17400 |
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Score: ______________ | |