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 July 07 2026
02:55:19 AM | Tuesday July 07 2026
02:55:19 AMFlip Answers |
| 1) | 398 * 402 = | | 1) 400 * 400 - 2 * 2 = 159996 |
| 2) | 392 * 408 = | | 2) 400 * 400 - 8 * 8 = 159936 |
| 3) | 190 * 210 = | | 3) 200 * 200 - 10 * 10 = 39900 |
| 4) | 210 * 190 = | | 4) 200 * 200 - 10 * 10 = 39900 |
| 5) | 195 * 205 = | | 5) 200 * 200 - 5 * 5 = 39975 |
| 6) | 399 * 401 = | | 6) 400 * 400 - 1 * 1 = 159999 |
| 7) | 392 * 408 = | | 7) 400 * 400 - 8 * 8 = 159936 |
| 8) | 192 * 208 = | | 8) 200 * 200 - 8 * 8 = 39936 |
| 9) | 293 * 307 = | | 9) 300 * 300 - 7 * 7 = 89951 |
| 10) | 309 * 291 = | | 10) 300 * 300 - 9 * 9 = 89919 |
| 11) | 243 * 68 - 68 * 43 = | | 11) ( 243 - 43) * 68 = 13600 |
| 12) | 89 * 250 - 89 * 50 = | | 12) ( 250 - 50) * 89 = 17800 |
| 13) | 141 * 92 - 92 * 41 = | | 13) ( 141 - 41) * 92 = 9200 |
| 14) | 136 * 63 - 36 * 63 = | | 14) ( 136 - 36) * 63 = 6300 |
| 15) | 63 * 30 + 37 * 30 = | | 15) ( 37 + 63) * 30 = 3000 |
| 16) | 34 * 56 + 56 * 66 = | | 16) ( 34 + 66) * 56 = 5600 |
| 17) | 50 * 29 + 50 * 29 = | | 17) ( 50 + 50) * 29 = 2900 |
| 18) | 36 * 236 - 36 * 36 = | | 18) ( 236 - 36) * 36 = 7200 |
| 19) | 53 * 97 + 47 * 97 = | | 19) ( 47 + 53) * 97 = 9700 |
| 20) | 24 * 252 - 52 * 24 = | | 20) ( 252 - 52) * 24 = 4800 |
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Score: ______________ | |
