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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Tuesday April 14 2026
08:42:36 AM | Tuesday April 14 2026
08:42:36 AMFlip Answers |
| 1) | 395 * 405 = | | 1) 400 * 400 - 5 * 5 = 159975 |
| 2) | 395 * 405 = | | 2) 400 * 400 - 5 * 5 = 159975 |
| 3) | 294 * 306 = | | 3) 300 * 300 - 6 * 6 = 89964 |
| 4) | 401 * 399 = | | 4) 400 * 400 - 1 * 1 = 159999 |
| 5) | 292 * 308 = | | 5) 300 * 300 - 8 * 8 = 89936 |
| 6) | 410 * 390 = | | 6) 400 * 400 - 10 * 10 = 159900 |
| 7) | 105 * 95 = | | 7) 100 * 100 - 5 * 5 = 9975 |
| 8) | 110 * 90 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 299 * 301 = | | 9) 300 * 300 - 1 * 1 = 89999 |
| 10) | 191 * 209 = | | 10) 200 * 200 - 9 * 9 = 39919 |
| 11) | 81 * 41 + 81 * 59 = | | 11) ( 59 + 41) * 81 = 8100 |
| 12) | 48 * 57 + 43 * 48 = | | 12) ( 57 + 43) * 48 = 4800 |
| 13) | 31 * 138 - 38 * 31 = | | 13) ( 138 - 38) * 31 = 3100 |
| 14) | 47 * 34 + 47 * 66 = | | 14) ( 34 + 66) * 47 = 4700 |
| 15) | 250 * 60 - 60 * 50 = | | 15) ( 250 - 50) * 60 = 12000 |
| 16) | 275 * 41 - 75 * 41 = | | 16) ( 275 - 75) * 41 = 8200 |
| 17) | 35 * 42 + 158 * 35 = | | 17) ( 158 + 42) * 35 = 7000 |
| 18) | 91 * 48 + 91 * 152 = | | 18) ( 152 + 48) * 91 = 18200 |
| 19) | 43 * 151 - 43 * 51 = | | 19) ( 151 - 51) * 43 = 4300 |
| 20) | 22 * 247 - 22 * 47 = | | 20) ( 247 - 47) * 22 = 4400 |
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Score: ______________ | |
