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 March 30 2026
08:37:12 AM | Monday March 30 2026
08:37:12 AMFlip Answers |
| 1) | 207 * 193 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 394 * 406 = | | 2) 400 * 400 - 6 * 6 = 159964 |
| 3) | 107 * 93 = | | 3) 100 * 100 - 7 * 7 = 9951 |
| 4) | 196 * 204 = | | 4) 200 * 200 - 4 * 4 = 39984 |
| 5) | 394 * 406 = | | 5) 400 * 400 - 6 * 6 = 159964 |
| 6) | 404 * 396 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 304 * 296 = | | 7) 300 * 300 - 4 * 4 = 89984 |
| 8) | 191 * 209 = | | 8) 200 * 200 - 9 * 9 = 39919 |
| 9) | 399 * 401 = | | 9) 400 * 400 - 1 * 1 = 159999 |
| 10) | 99 * 101 = | | 10) 100 * 100 - 1 * 1 = 9999 |
| 11) | 66 * 60 + 66 * 40 = | | 11) ( 60 + 40) * 66 = 6600 |
| 12) | 142 * 77 + 77 * 58 = | | 12) ( 142 + 58) * 77 = 15400 |
| 13) | 48 * 78 + 52 * 78 = | | 13) ( 52 + 48) * 78 = 7800 |
| 14) | 138 * 79 - 38 * 79 = | | 14) ( 138 - 38) * 79 = 7900 |
| 15) | 243 * 40 - 40 * 43 = | | 15) ( 243 - 43) * 40 = 8000 |
| 16) | 161 * 64 + 64 * 39 = | | 16) ( 161 + 39) * 64 = 12800 |
| 17) | 35 * 65 + 65 * 65 = | | 17) ( 65 + 35) * 65 = 6500 |
| 18) | 35 * 46 + 54 * 35 = | | 18) ( 54 + 46) * 35 = 3500 |
| 19) | 97 * 71 + 97 * 129 = | | 19) ( 129 + 71) * 97 = 19400 |
| 20) | 41 * 78 + 59 * 78 = | | 20) ( 59 + 41) * 78 = 7800 |
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Score: ______________ | |
