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 February 10 2026
05:11:02 PM | Tuesday February 10 2026
05:11:02 PMFlip Answers |
| 1) | 399 * 401 = | | 1) 400 * 400 - 1 * 1 = 159999 |
| 2) | 308 * 292 = | | 2) 300 * 300 - 8 * 8 = 89936 |
| 3) | 397 * 403 = | | 3) 400 * 400 - 3 * 3 = 159991 |
| 4) | 410 * 390 = | | 4) 400 * 400 - 10 * 10 = 159900 |
| 5) | 405 * 395 = | | 5) 400 * 400 - 5 * 5 = 159975 |
| 6) | 101 * 99 = | | 6) 100 * 100 - 1 * 1 = 9999 |
| 7) | 108 * 92 = | | 7) 100 * 100 - 8 * 8 = 9936 |
| 8) | 406 * 394 = | | 8) 400 * 400 - 6 * 6 = 159964 |
| 9) | 302 * 298 = | | 9) 300 * 300 - 2 * 2 = 89996 |
| 10) | 408 * 392 = | | 10) 400 * 400 - 8 * 8 = 159936 |
| 11) | 58 * 93 + 93 * 42 = | | 11) ( 58 + 42) * 93 = 9300 |
| 12) | 88 * 37 + 88 * 63 = | | 12) ( 37 + 63) * 88 = 8800 |
| 13) | 50 * 175 - 50 * 75 = | | 13) ( 175 - 75) * 50 = 5000 |
| 14) | 85 * 162 - 62 * 85 = | | 14) ( 162 - 62) * 85 = 8500 |
| 15) | 25 * 240 - 25 * 40 = | | 15) ( 240 - 40) * 25 = 5000 |
| 16) | 140 * 56 - 40 * 56 = | | 16) ( 140 - 40) * 56 = 5600 |
| 17) | 36 * 93 + 164 * 93 = | | 17) ( 164 + 36) * 93 = 18600 |
| 18) | 257 * 52 - 57 * 52 = | | 18) ( 257 - 57) * 52 = 10400 |
| 19) | 42 * 65 + 42 * 135 = | | 19) ( 135 + 65) * 42 = 8400 |
| 20) | 24 * 250 - 50 * 24 = | | 20) ( 250 - 50) * 24 = 4800 |
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Score: ______________ | |
