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 02 2026
05:51:14 PM | Monday March 02 2026
05:51:14 PMFlip Answers |
| 1) | 102 * 98 = | | 1) 100 * 100 - 2 * 2 = 9996 |
| 2) | 296 * 304 = | | 2) 300 * 300 - 4 * 4 = 89984 |
| 3) | 395 * 405 = | | 3) 400 * 400 - 5 * 5 = 159975 |
| 4) | 397 * 403 = | | 4) 400 * 400 - 3 * 3 = 159991 |
| 5) | 209 * 191 = | | 5) 200 * 200 - 9 * 9 = 39919 |
| 6) | 399 * 401 = | | 6) 400 * 400 - 1 * 1 = 159999 |
| 7) | 395 * 405 = | | 7) 400 * 400 - 5 * 5 = 159975 |
| 8) | 99 * 101 = | | 8) 100 * 100 - 1 * 1 = 9999 |
| 9) | 296 * 304 = | | 9) 300 * 300 - 4 * 4 = 89984 |
| 10) | 191 * 209 = | | 10) 200 * 200 - 9 * 9 = 39919 |
| 11) | 245 * 43 - 43 * 45 = | | 11) ( 245 - 45) * 43 = 8600 |
| 12) | 63 * 165 + 35 * 63 = | | 12) ( 165 + 35) * 63 = 12600 |
| 13) | 70 * 64 + 64 * 130 = | | 13) ( 130 + 70) * 64 = 12800 |
| 14) | 38 * 61 + 61 * 62 = | | 14) ( 62 + 38) * 61 = 6100 |
| 15) | 142 * 42 - 42 * 42 = | | 15) ( 142 - 42) * 42 = 4200 |
| 16) | 80 * 147 - 80 * 47 = | | 16) ( 147 - 47) * 80 = 8000 |
| 17) | 142 * 39 - 39 * 42 = | | 17) ( 142 - 42) * 39 = 3900 |
| 18) | 39 * 175 - 39 * 75 = | | 18) ( 175 - 75) * 39 = 3900 |
| 19) | 241 * 85 - 85 * 41 = | | 19) ( 241 - 41) * 85 = 17000 |
| 20) | 238 * 62 - 38 * 62 = | | 20) ( 238 - 38) * 62 = 12400 |
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Score: ______________ | |
