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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Monday May 11 2026
05:02:38 AM | Monday May 11 2026
05:02:38 AMFlip Answers |
| 1) | 402 * 398 = | | 1) 400 * 400 - 2 * 2 = 159996 |
| 2) | 194 * 206 = | | 2) 200 * 200 - 6 * 6 = 39964 |
| 3) | 190 * 210 = | | 3) 200 * 200 - 10 * 10 = 39900 |
| 4) | 193 * 207 = | | 4) 200 * 200 - 7 * 7 = 39951 |
| 5) | 390 * 410 = | | 5) 400 * 400 - 10 * 10 = 159900 |
| 6) | 396 * 404 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 404 * 396 = | | 7) 400 * 400 - 4 * 4 = 159984 |
| 8) | 399 * 401 = | | 8) 400 * 400 - 1 * 1 = 159999 |
| 9) | 191 * 209 = | | 9) 200 * 200 - 9 * 9 = 39919 |
| 10) | 292 * 308 = | | 10) 300 * 300 - 8 * 8 = 89936 |
| 11) | 93 * 48 + 93 * 52 = | | 11) ( 48 + 52) * 93 = 9300 |
| 12) | 148 * 63 + 52 * 63 = | | 12) ( 148 + 52) * 63 = 12600 |
| 13) | 246 * 34 - 46 * 34 = | | 13) ( 246 - 46) * 34 = 6800 |
| 14) | 52 * 162 - 52 * 62 = | | 14) ( 162 - 62) * 52 = 5200 |
| 15) | 54 * 37 + 54 * 63 = | | 15) ( 63 + 37) * 54 = 5400 |
| 16) | 152 * 53 - 53 * 52 = | | 16) ( 152 - 52) * 53 = 5300 |
| 17) | 31 * 73 + 31 * 127 = | | 17) ( 127 + 73) * 31 = 6200 |
| 18) | 73 * 60 + 40 * 73 = | | 18) ( 60 + 40) * 73 = 7300 |
| 19) | 71 * 53 + 129 * 53 = | | 19) ( 129 + 71) * 53 = 10600 |
| 20) | 79 * 127 + 79 * 73 = | | 20) ( 127 + 73) * 79 = 15800 |
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Score: ______________ | |
