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 September 01 2026
10:54:45 AM | Tuesday September 01 2026
10:54:45 AMFlip Answers |
| 1) | 397 * 403 = | | 1) 400 * 400 - 3 * 3 = 159991 |
| 2) | 95 * 105 = | | 2) 100 * 100 - 5 * 5 = 9975 |
| 3) | 404 * 396 = | | 3) 400 * 400 - 4 * 4 = 159984 |
| 4) | 402 * 398 = | | 4) 400 * 400 - 2 * 2 = 159996 |
| 5) | 96 * 104 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 406 * 394 = | | 6) 400 * 400 - 6 * 6 = 159964 |
| 7) | 291 * 309 = | | 7) 300 * 300 - 9 * 9 = 89919 |
| 8) | 398 * 402 = | | 8) 400 * 400 - 2 * 2 = 159996 |
| 9) | 309 * 291 = | | 9) 300 * 300 - 9 * 9 = 89919 |
| 10) | 110 * 90 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 136 * 75 - 75 * 36 = | | 11) ( 136 - 36) * 75 = 7500 |
| 12) | 70 * 143 - 70 * 43 = | | 12) ( 143 - 43) * 70 = 7000 |
| 13) | 158 * 53 + 53 * 42 = | | 13) ( 158 + 42) * 53 = 10600 |
| 14) | 172 * 39 - 39 * 72 = | | 14) ( 172 - 72) * 39 = 3900 |
| 15) | 42 * 51 + 58 * 51 = | | 15) ( 58 + 42) * 51 = 5100 |
| 16) | 33 * 274 - 74 * 33 = | | 16) ( 274 - 74) * 33 = 6600 |
| 17) | 130 * 61 + 70 * 61 = | | 17) ( 130 + 70) * 61 = 12200 |
| 18) | 48 * 37 + 163 * 48 = | | 18) ( 163 + 37) * 48 = 9600 |
| 19) | 153 * 69 - 53 * 69 = | | 19) ( 153 - 53) * 69 = 6900 |
| 20) | 60 * 63 + 40 * 63 = | | 20) ( 60 + 40) * 63 = 6300 |
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Score: ______________ | |
