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 December 02 2025 01:32:40 AM | Tuesday December 02 2025 01:32:40 AMFlip Answers |
| 1) | 395 * 405 = | | 1) 400 * 400 - 5 * 5 = 159975 |
| 2) | 404 * 396 = | | 2) 400 * 400 - 4 * 4 = 159984 |
| 3) | 308 * 292 = | | 3) 300 * 300 - 8 * 8 = 89936 |
| 4) | 397 * 403 = | | 4) 400 * 400 - 3 * 3 = 159991 |
| 5) | 398 * 402 = | | 5) 400 * 400 - 2 * 2 = 159996 |
| 6) | 393 * 407 = | | 6) 400 * 400 - 7 * 7 = 159951 |
| 7) | 293 * 307 = | | 7) 300 * 300 - 7 * 7 = 89951 |
| 8) | 393 * 407 = | | 8) 400 * 400 - 7 * 7 = 159951 |
| 9) | 299 * 301 = | | 9) 300 * 300 - 1 * 1 = 89999 |
| 10) | 208 * 192 = | | 10) 200 * 200 - 8 * 8 = 39936 |
| 11) | 69 * 250 - 50 * 69 = | | 11) ( 250 - 50) * 69 = 13800 |
| 12) | 143 * 66 + 66 * 57 = | | 12) ( 143 + 57) * 66 = 13200 |
| 13) | 83 * 165 - 83 * 65 = | | 13) ( 165 - 65) * 83 = 8300 |
| 14) | 34 * 128 + 34 * 72 = | | 14) ( 128 + 72) * 34 = 6800 |
| 15) | 165 * 85 - 85 * 65 = | | 15) ( 165 - 65) * 85 = 8500 |
| 16) | 32 * 39 + 32 * 161 = | | 16) ( 161 + 39) * 32 = 6400 |
| 17) | 50 * 72 + 50 * 128 = | | 17) ( 128 + 72) * 50 = 10000 |
| 18) | 158 * 25 - 25 * 58 = | | 18) ( 158 - 58) * 25 = 2500 |
| 19) | 41 * 35 + 35 * 159 = | | 19) ( 159 + 41) * 35 = 7000 |
| 20) | 59 * 52 + 141 * 52 = | | 20) ( 141 + 59) * 52 = 10400 |
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Score: ______________ | |