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 April 10 2026 08:59:49 AM | Friday April 10 2026 08:59:49 AMFlip Answers |
| 1) | 193 * 207 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 108 * 92 = | | 2) 100 * 100 - 8 * 8 = 9936 |
| 3) | 399 * 401 = | | 3) 400 * 400 - 1 * 1 = 159999 |
| 4) | 308 * 292 = | | 4) 300 * 300 - 8 * 8 = 89936 |
| 5) | 403 * 397 = | | 5) 400 * 400 - 3 * 3 = 159991 |
| 6) | 96 * 104 = | | 6) 100 * 100 - 4 * 4 = 9984 |
| 7) | 195 * 205 = | | 7) 200 * 200 - 5 * 5 = 39975 |
| 8) | 398 * 402 = | | 8) 400 * 400 - 2 * 2 = 159996 |
| 9) | 202 * 198 = | | 9) 200 * 200 - 2 * 2 = 39996 |
| 10) | 98 * 102 = | | 10) 100 * 100 - 2 * 2 = 9996 |
| 11) | 57 * 67 + 43 * 67 = | | 11) ( 43 + 57) * 67 = 6700 |
| 12) | 41 * 150 + 50 * 41 = | | 12) ( 150 + 50) * 41 = 8200 |
| 13) | 61 * 243 - 43 * 61 = | | 13) ( 243 - 43) * 61 = 12200 |
| 14) | 49 * 49 + 51 * 49 = | | 14) ( 49 + 51) * 49 = 4900 |
| 15) | 70 * 151 + 49 * 70 = | | 15) ( 151 + 49) * 70 = 14000 |
| 16) | 53 * 36 + 53 * 64 = | | 16) ( 64 + 36) * 53 = 5300 |
| 17) | 151 * 59 - 51 * 59 = | | 17) ( 151 - 51) * 59 = 5900 |
| 18) | 53 * 170 - 53 * 70 = | | 18) ( 170 - 70) * 53 = 5300 |
| 19) | 237 * 49 - 37 * 49 = | | 19) ( 237 - 37) * 49 = 9800 |
| 20) | 175 * 40 - 75 * 40 = | | 20) ( 175 - 75) * 40 = 4000 |
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Score: ______________ | |