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 08 2026
02:55:31 PM | Thursday October 08 2026
02:55:31 PMFlip Answers |
| 1) | 292 * 308 = | | 1) 300 * 300 - 8 * 8 = 89936 |
| 2) | 303 * 297 = | | 2) 300 * 300 - 3 * 3 = 89991 |
| 3) | 98 * 102 = | | 3) 100 * 100 - 2 * 2 = 9996 |
| 4) | 99 * 101 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 408 * 392 = | | 5) 400 * 400 - 8 * 8 = 159936 |
| 6) | 206 * 194 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 301 * 299 = | | 7) 300 * 300 - 1 * 1 = 89999 |
| 8) | 403 * 397 = | | 8) 400 * 400 - 3 * 3 = 159991 |
| 9) | 291 * 309 = | | 9) 300 * 300 - 9 * 9 = 89919 |
| 10) | 299 * 301 = | | 10) 300 * 300 - 1 * 1 = 89999 |
| 11) | 129 * 61 + 61 * 71 = | | 11) ( 129 + 71) * 61 = 12200 |
| 12) | 67 * 269 - 69 * 67 = | | 12) ( 269 - 69) * 67 = 13400 |
| 13) | 25 * 263 - 63 * 25 = | | 13) ( 263 - 63) * 25 = 5000 |
| 14) | 69 * 163 - 69 * 63 = | | 14) ( 163 - 63) * 69 = 6900 |
| 15) | 72 * 76 + 76 * 28 = | | 15) ( 28 + 72) * 76 = 7600 |
| 16) | 61 * 139 - 39 * 61 = | | 16) ( 139 - 39) * 61 = 6100 |
| 17) | 75 * 86 + 125 * 86 = | | 17) ( 125 + 75) * 86 = 17200 |
| 18) | 78 * 171 - 78 * 71 = | | 18) ( 171 - 71) * 78 = 7800 |
| 19) | 151 * 34 - 51 * 34 = | | 19) ( 151 - 51) * 34 = 3400 |
| 20) | 45 * 50 + 55 * 50 = | | 20) ( 55 + 45) * 50 = 5000 |
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Score: ______________ | |
