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 March 22 2026
04:54:34 AM | Sunday March 22 2026
04:54:34 AMFlip Answers |
| 1) | 108 * 92 = | | 1) 100 * 100 - 8 * 8 = 9936 |
| 2) | 193 * 207 = | | 2) 200 * 200 - 7 * 7 = 39951 |
| 3) | 390 * 410 = | | 3) 400 * 400 - 10 * 10 = 159900 |
| 4) | 396 * 404 = | | 4) 400 * 400 - 4 * 4 = 159984 |
| 5) | 110 * 90 = | | 5) 100 * 100 - 10 * 10 = 9900 |
| 6) | 208 * 192 = | | 6) 200 * 200 - 8 * 8 = 39936 |
| 7) | 91 * 109 = | | 7) 100 * 100 - 9 * 9 = 9919 |
| 8) | 309 * 291 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 196 * 204 = | | 9) 200 * 200 - 4 * 4 = 39984 |
| 10) | 396 * 404 = | | 10) 400 * 400 - 4 * 4 = 159984 |
| 11) | 40 * 169 - 40 * 69 = | | 11) ( 169 - 69) * 40 = 4000 |
| 12) | 39 * 27 + 27 * 61 = | | 12) ( 61 + 39) * 27 = 2700 |
| 13) | 72 * 136 + 72 * 64 = | | 13) ( 136 + 64) * 72 = 14400 |
| 14) | 87 * 152 - 52 * 87 = | | 14) ( 152 - 52) * 87 = 8700 |
| 15) | 53 * 58 + 53 * 42 = | | 15) ( 58 + 42) * 53 = 5300 |
| 16) | 68 * 267 - 67 * 68 = | | 16) ( 267 - 67) * 68 = 13600 |
| 17) | 238 * 54 - 38 * 54 = | | 17) ( 238 - 38) * 54 = 10800 |
| 18) | 61 * 169 - 61 * 69 = | | 18) ( 169 - 69) * 61 = 6100 |
| 19) | 61 * 251 - 51 * 61 = | | 19) ( 251 - 51) * 61 = 12200 |
| 20) | 242 * 42 - 42 * 42 = | | 20) ( 242 - 42) * 42 = 8400 |
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Score: ______________ | |
