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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Thursday October 15 2026
07:21:17 PM | Thursday October 15 2026
07:21:17 PMFlip Answers |
| 1) | 202 * 198 = | | 1) 200 * 200 - 2 * 2 = 39996 |
| 2) | 392 * 408 = | | 2) 400 * 400 - 8 * 8 = 159936 |
| 3) | 306 * 294 = | | 3) 300 * 300 - 6 * 6 = 89964 |
| 4) | 395 * 405 = | | 4) 400 * 400 - 5 * 5 = 159975 |
| 5) | 409 * 391 = | | 5) 400 * 400 - 9 * 9 = 159919 |
| 6) | 104 * 96 = | | 6) 100 * 100 - 4 * 4 = 9984 |
| 7) | 308 * 292 = | | 7) 300 * 300 - 8 * 8 = 89936 |
| 8) | 108 * 92 = | | 8) 100 * 100 - 8 * 8 = 9936 |
| 9) | 291 * 309 = | | 9) 300 * 300 - 9 * 9 = 89919 |
| 10) | 94 * 106 = | | 10) 100 * 100 - 6 * 6 = 9964 |
| 11) | 170 * 69 - 70 * 69 = | | 11) ( 170 - 70) * 69 = 6900 |
| 12) | 43 * 144 + 43 * 56 = | | 12) ( 144 + 56) * 43 = 8600 |
| 13) | 52 * 266 - 66 * 52 = | | 13) ( 266 - 66) * 52 = 10400 |
| 14) | 87 * 139 - 87 * 39 = | | 14) ( 139 - 39) * 87 = 8700 |
| 15) | 235 * 75 - 35 * 75 = | | 15) ( 235 - 35) * 75 = 15000 |
| 16) | 89 * 161 - 61 * 89 = | | 16) ( 161 - 61) * 89 = 8900 |
| 17) | 158 * 67 + 67 * 42 = | | 17) ( 158 + 42) * 67 = 13400 |
| 18) | 96 * 151 - 51 * 96 = | | 18) ( 151 - 51) * 96 = 9600 |
| 19) | 82 * 267 - 82 * 67 = | | 19) ( 267 - 67) * 82 = 16400 |
| 20) | 79 * 152 - 52 * 79 = | | 20) ( 152 - 52) * 79 = 7900 |
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Score: ______________ | |
