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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Tuesday May 26 2026
11:27:58 AM | Tuesday May 26 2026
11:27:58 AMFlip Answers |
| 1) | 109 * 91 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 305 * 295 = | | 2) 300 * 300 - 5 * 5 = 89975 |
| 3) | 297 * 303 = | | 3) 300 * 300 - 3 * 3 = 89991 |
| 4) | 104 * 96 = | | 4) 100 * 100 - 4 * 4 = 9984 |
| 5) | 399 * 401 = | | 5) 400 * 400 - 1 * 1 = 159999 |
| 6) | 294 * 306 = | | 6) 300 * 300 - 6 * 6 = 89964 |
| 7) | 398 * 402 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 395 * 405 = | | 8) 400 * 400 - 5 * 5 = 159975 |
| 9) | 106 * 94 = | | 9) 100 * 100 - 6 * 6 = 9964 |
| 10) | 402 * 398 = | | 10) 400 * 400 - 2 * 2 = 159996 |
| 11) | 80 * 267 - 67 * 80 = | | 11) ( 267 - 67) * 80 = 16000 |
| 12) | 55 * 34 + 45 * 34 = | | 12) ( 45 + 55) * 34 = 3400 |
| 13) | 54 * 140 - 40 * 54 = | | 13) ( 140 - 40) * 54 = 5400 |
| 14) | 62 * 140 - 40 * 62 = | | 14) ( 140 - 40) * 62 = 6200 |
| 15) | 126 * 23 + 23 * 74 = | | 15) ( 126 + 74) * 23 = 4600 |
| 16) | 70 * 152 - 70 * 52 = | | 16) ( 152 - 52) * 70 = 7000 |
| 17) | 148 * 68 - 48 * 68 = | | 17) ( 148 - 48) * 68 = 6800 |
| 18) | 269 * 40 - 69 * 40 = | | 18) ( 269 - 69) * 40 = 8000 |
| 19) | 255 * 90 - 90 * 55 = | | 19) ( 255 - 55) * 90 = 18000 |
| 20) | 24 * 68 + 132 * 24 = | | 20) ( 132 + 68) * 24 = 4800 |
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Score: ______________ | |
