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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Saturday June 27 2026
02:42:49 PM | Saturday June 27 2026
02:42:49 PMFlip Answers |
| 1) | 207 * 193 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 295 * 305 = | | 2) 300 * 300 - 5 * 5 = 89975 |
| 3) | 397 * 403 = | | 3) 400 * 400 - 3 * 3 = 159991 |
| 4) | 203 * 197 = | | 4) 200 * 200 - 3 * 3 = 39991 |
| 5) | 396 * 404 = | | 5) 400 * 400 - 4 * 4 = 159984 |
| 6) | 303 * 297 = | | 6) 300 * 300 - 3 * 3 = 89991 |
| 7) | 304 * 296 = | | 7) 300 * 300 - 4 * 4 = 89984 |
| 8) | 90 * 110 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 296 * 304 = | | 9) 300 * 300 - 4 * 4 = 89984 |
| 10) | 298 * 302 = | | 10) 300 * 300 - 2 * 2 = 89996 |
| 11) | 64 * 246 - 46 * 64 = | | 11) ( 246 - 46) * 64 = 12800 |
| 12) | 83 * 161 + 39 * 83 = | | 12) ( 161 + 39) * 83 = 16600 |
| 13) | 65 * 91 + 35 * 91 = | | 13) ( 65 + 35) * 91 = 9100 |
| 14) | 50 * 69 + 31 * 50 = | | 14) ( 31 + 69) * 50 = 5000 |
| 15) | 70 * 135 - 70 * 35 = | | 15) ( 135 - 35) * 70 = 7000 |
| 16) | 157 * 74 - 57 * 74 = | | 16) ( 157 - 57) * 74 = 7400 |
| 17) | 61 * 44 + 44 * 39 = | | 17) ( 61 + 39) * 44 = 4400 |
| 18) | 48 * 23 + 52 * 23 = | | 18) ( 48 + 52) * 23 = 2300 |
| 19) | 136 * 67 - 67 * 36 = | | 19) ( 136 - 36) * 67 = 6700 |
| 20) | 48 * 25 + 25 * 152 = | | 20) ( 152 + 48) * 25 = 5000 |
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Score: ______________ | |
