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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Wednesday November 05 2025
08:53:49 PM | Wednesday November 05 2025
08:53:49 PMFlip Answers |
| 1) | 291 * 309 = | | 1) 300 * 300 - 9 * 9 = 89919 |
| 2) | 310 * 290 = | | 2) 300 * 300 - 10 * 10 = 89900 |
| 3) | 410 * 390 = | | 3) 400 * 400 - 10 * 10 = 159900 |
| 4) | 210 * 190 = | | 4) 200 * 200 - 10 * 10 = 39900 |
| 5) | 304 * 296 = | | 5) 300 * 300 - 4 * 4 = 89984 |
| 6) | 404 * 396 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 94 * 106 = | | 7) 100 * 100 - 6 * 6 = 9964 |
| 8) | 106 * 94 = | | 8) 100 * 100 - 6 * 6 = 9964 |
| 9) | 395 * 405 = | | 9) 400 * 400 - 5 * 5 = 159975 |
| 10) | 309 * 291 = | | 10) 300 * 300 - 9 * 9 = 89919 |
| 11) | 90 * 235 - 35 * 90 = | | 11) ( 235 - 35) * 90 = 18000 |
| 12) | 48 * 142 + 58 * 48 = | | 12) ( 142 + 58) * 48 = 9600 |
| 13) | 247 * 96 - 47 * 96 = | | 13) ( 247 - 47) * 96 = 19200 |
| 14) | 64 * 42 + 58 * 64 = | | 14) ( 42 + 58) * 64 = 6400 |
| 15) | 139 * 97 - 97 * 39 = | | 15) ( 139 - 39) * 97 = 9700 |
| 16) | 80 * 266 - 80 * 66 = | | 16) ( 266 - 66) * 80 = 16000 |
| 17) | 94 * 50 + 50 * 94 = | | 17) ( 50 + 50) * 94 = 9400 |
| 18) | 131 * 46 + 69 * 46 = | | 18) ( 131 + 69) * 46 = 9200 |
| 19) | 34 * 42 + 34 * 58 = | | 19) ( 58 + 42) * 34 = 3400 |
| 20) | 67 * 55 + 55 * 133 = | | 20) ( 133 + 67) * 55 = 11000 |
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Score: ______________ | |
