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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Monday March 09 2026
09:53:27 PM | Monday March 09 2026
09:53:27 PMFlip Answers |
| 1) | 199 * 201 = | | 1) 200 * 200 - 1 * 1 = 39999 |
| 2) | 390 * 410 = | | 2) 400 * 400 - 10 * 10 = 159900 |
| 3) | 392 * 408 = | | 3) 400 * 400 - 8 * 8 = 159936 |
| 4) | 91 * 109 = | | 4) 100 * 100 - 9 * 9 = 9919 |
| 5) | 304 * 296 = | | 5) 300 * 300 - 4 * 4 = 89984 |
| 6) | 410 * 390 = | | 6) 400 * 400 - 10 * 10 = 159900 |
| 7) | 301 * 299 = | | 7) 300 * 300 - 1 * 1 = 89999 |
| 8) | 294 * 306 = | | 8) 300 * 300 - 6 * 6 = 89964 |
| 9) | 298 * 302 = | | 9) 300 * 300 - 2 * 2 = 89996 |
| 10) | 98 * 102 = | | 10) 100 * 100 - 2 * 2 = 9996 |
| 11) | 161 * 26 + 39 * 26 = | | 11) ( 161 + 39) * 26 = 5200 |
| 12) | 52 * 175 - 52 * 75 = | | 12) ( 175 - 75) * 52 = 5200 |
| 13) | 71 * 264 - 71 * 64 = | | 13) ( 264 - 64) * 71 = 14200 |
| 14) | 80 * 235 - 80 * 35 = | | 14) ( 235 - 35) * 80 = 16000 |
| 15) | 239 * 40 - 40 * 39 = | | 15) ( 239 - 39) * 40 = 8000 |
| 16) | 82 * 138 + 82 * 62 = | | 16) ( 138 + 62) * 82 = 16400 |
| 17) | 163 * 45 + 45 * 37 = | | 17) ( 163 + 37) * 45 = 9000 |
| 18) | 32 * 161 + 39 * 32 = | | 18) ( 161 + 39) * 32 = 6400 |
| 19) | 21 * 65 + 135 * 21 = | | 19) ( 135 + 65) * 21 = 4200 |
| 20) | 89 * 64 + 89 * 36 = | | 20) ( 36 + 64) * 89 = 8900 |
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Score: ______________ | |
