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 November 18 2025
10:49:52 AM | Tuesday November 18 2025
10:49:52 AMFlip Answers |
| 1) | 310 * 290 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 90 * 110 = | | 2) 100 * 100 - 10 * 10 = 9900 |
| 3) | 292 * 308 = | | 3) 300 * 300 - 8 * 8 = 89936 |
| 4) | 395 * 405 = | | 4) 400 * 400 - 5 * 5 = 159975 |
| 5) | 390 * 410 = | | 5) 400 * 400 - 10 * 10 = 159900 |
| 6) | 198 * 202 = | | 6) 200 * 200 - 2 * 2 = 39996 |
| 7) | 202 * 198 = | | 7) 200 * 200 - 2 * 2 = 39996 |
| 8) | 394 * 406 = | | 8) 400 * 400 - 6 * 6 = 159964 |
| 9) | 205 * 195 = | | 9) 200 * 200 - 5 * 5 = 39975 |
| 10) | 295 * 305 = | | 10) 300 * 300 - 5 * 5 = 89975 |
| 11) | 26 * 43 + 26 * 157 = | | 11) ( 157 + 43) * 26 = 5200 |
| 12) | 45 * 175 - 45 * 75 = | | 12) ( 175 - 75) * 45 = 4500 |
| 13) | 79 * 139 - 79 * 39 = | | 13) ( 139 - 39) * 79 = 7900 |
| 14) | 51 * 42 + 58 * 51 = | | 14) ( 42 + 58) * 51 = 5100 |
| 15) | 240 * 32 - 40 * 32 = | | 15) ( 240 - 40) * 32 = 6400 |
| 16) | 256 * 67 - 56 * 67 = | | 16) ( 256 - 56) * 67 = 13400 |
| 17) | 89 * 46 + 154 * 89 = | | 17) ( 154 + 46) * 89 = 17800 |
| 18) | 41 * 41 + 59 * 41 = | | 18) ( 59 + 41) * 41 = 4100 |
| 19) | 50 * 61 + 39 * 50 = | | 19) ( 39 + 61) * 50 = 5000 |
| 20) | 65 * 37 + 37 * 35 = | | 20) ( 65 + 35) * 37 = 3700 |
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Score: ______________ | |
