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 August 31 2026
10:43:09 AM | Monday August 31 2026
10:43:09 AMFlip Answers |
| 1) | 102 * 98 = | | 1) 100 * 100 - 2 * 2 = 9996 |
| 2) | 407 * 393 = | | 2) 400 * 400 - 7 * 7 = 159951 |
| 3) | 401 * 399 = | | 3) 400 * 400 - 1 * 1 = 159999 |
| 4) | 292 * 308 = | | 4) 300 * 300 - 8 * 8 = 89936 |
| 5) | 396 * 404 = | | 5) 400 * 400 - 4 * 4 = 159984 |
| 6) | 107 * 93 = | | 6) 100 * 100 - 7 * 7 = 9951 |
| 7) | 296 * 304 = | | 7) 300 * 300 - 4 * 4 = 89984 |
| 8) | 193 * 207 = | | 8) 200 * 200 - 7 * 7 = 39951 |
| 9) | 397 * 403 = | | 9) 400 * 400 - 3 * 3 = 159991 |
| 10) | 101 * 99 = | | 10) 100 * 100 - 1 * 1 = 9999 |
| 11) | 46 * 50 + 46 * 50 = | | 11) ( 50 + 50) * 46 = 4600 |
| 12) | 57 * 155 - 55 * 57 = | | 12) ( 155 - 55) * 57 = 5700 |
| 13) | 32 * 49 + 68 * 49 = | | 13) ( 32 + 68) * 49 = 4900 |
| 14) | 38 * 82 + 82 * 62 = | | 14) ( 62 + 38) * 82 = 8200 |
| 15) | 57 * 51 + 57 * 49 = | | 15) ( 49 + 51) * 57 = 5700 |
| 16) | 21 * 170 - 70 * 21 = | | 16) ( 170 - 70) * 21 = 2100 |
| 17) | 45 * 53 + 45 * 47 = | | 17) ( 53 + 47) * 45 = 4500 |
| 18) | 260 * 62 - 62 * 60 = | | 18) ( 260 - 60) * 62 = 12400 |
| 19) | 62 * 30 + 30 * 38 = | | 19) ( 62 + 38) * 30 = 3000 |
| 20) | 70 * 34 + 70 * 66 = | | 20) ( 34 + 66) * 70 = 7000 |
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Score: ______________ | |
