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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Sunday November 08 2026
01:03:32 PM | Sunday November 08 2026
01:03:32 PMFlip Answers |
| 1) | 396 * 404 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 392 * 408 = | | 2) 400 * 400 - 8 * 8 = 159936 |
| 3) | 104 * 96 = | | 3) 100 * 100 - 4 * 4 = 9984 |
| 4) | 399 * 401 = | | 4) 400 * 400 - 1 * 1 = 159999 |
| 5) | 291 * 309 = | | 5) 300 * 300 - 9 * 9 = 89919 |
| 6) | 291 * 309 = | | 6) 300 * 300 - 9 * 9 = 89919 |
| 7) | 306 * 294 = | | 7) 300 * 300 - 6 * 6 = 89964 |
| 8) | 93 * 107 = | | 8) 100 * 100 - 7 * 7 = 9951 |
| 9) | 191 * 209 = | | 9) 200 * 200 - 9 * 9 = 39919 |
| 10) | 299 * 301 = | | 10) 300 * 300 - 1 * 1 = 89999 |
| 11) | 75 * 48 + 52 * 75 = | | 11) ( 52 + 48) * 75 = 7500 |
| 12) | 155 * 36 - 55 * 36 = | | 12) ( 155 - 55) * 36 = 3600 |
| 13) | 97 * 57 + 143 * 97 = | | 13) ( 143 + 57) * 97 = 19400 |
| 14) | 61 * 72 + 39 * 72 = | | 14) ( 61 + 39) * 72 = 7200 |
| 15) | 252 * 39 - 52 * 39 = | | 15) ( 252 - 52) * 39 = 7800 |
| 16) | 239 * 42 - 42 * 39 = | | 16) ( 239 - 39) * 42 = 8400 |
| 17) | 273 * 58 - 58 * 73 = | | 17) ( 273 - 73) * 58 = 11600 |
| 18) | 61 * 165 - 61 * 65 = | | 18) ( 165 - 65) * 61 = 6100 |
| 19) | 49 * 82 + 51 * 82 = | | 19) ( 51 + 49) * 82 = 8200 |
| 20) | 51 * 36 + 64 * 51 = | | 20) ( 36 + 64) * 51 = 5100 |
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Score: ______________ | |
