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 January 11 2026
02:55:13 AM | Sunday January 11 2026
02:55:13 AMFlip Answers |
| 1) | 410 * 390 = | | 1) 400 * 400 - 10 * 10 = 159900 |
| 2) | 206 * 194 = | | 2) 200 * 200 - 6 * 6 = 39964 |
| 3) | 297 * 303 = | | 3) 300 * 300 - 3 * 3 = 89991 |
| 4) | 110 * 90 = | | 4) 100 * 100 - 10 * 10 = 9900 |
| 5) | 401 * 399 = | | 5) 400 * 400 - 1 * 1 = 159999 |
| 6) | 196 * 204 = | | 6) 200 * 200 - 4 * 4 = 39984 |
| 7) | 392 * 408 = | | 7) 400 * 400 - 8 * 8 = 159936 |
| 8) | 110 * 90 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 405 * 395 = | | 9) 400 * 400 - 5 * 5 = 159975 |
| 10) | 210 * 190 = | | 10) 200 * 200 - 10 * 10 = 39900 |
| 11) | 236 * 46 - 36 * 46 = | | 11) ( 236 - 36) * 46 = 9200 |
| 12) | 137 * 84 + 63 * 84 = | | 12) ( 137 + 63) * 84 = 16800 |
| 13) | 51 * 70 + 49 * 70 = | | 13) ( 51 + 49) * 70 = 7000 |
| 14) | 83 * 173 - 73 * 83 = | | 14) ( 173 - 73) * 83 = 8300 |
| 15) | 245 * 88 - 88 * 45 = | | 15) ( 245 - 45) * 88 = 17600 |
| 16) | 73 * 63 + 37 * 73 = | | 16) ( 37 + 63) * 73 = 7300 |
| 17) | 60 * 257 - 57 * 60 = | | 17) ( 257 - 57) * 60 = 12000 |
| 18) | 59 * 75 + 41 * 75 = | | 18) ( 41 + 59) * 75 = 7500 |
| 19) | 64 * 58 + 58 * 36 = | | 19) ( 64 + 36) * 58 = 5800 |
| 20) | 54 * 35 + 46 * 35 = | | 20) ( 54 + 46) * 35 = 3500 |
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Score: ______________ | |
