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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Sunday May 03 2026
05:39:38 PM | Sunday May 03 2026
05:39:38 PMFlip Answers |
| 1) | 210 * 190 = | | 1) 200 * 200 - 10 * 10 = 39900 |
| 2) | 101 * 99 = | | 2) 100 * 100 - 1 * 1 = 9999 |
| 3) | 307 * 293 = | | 3) 300 * 300 - 7 * 7 = 89951 |
| 4) | 97 * 103 = | | 4) 100 * 100 - 3 * 3 = 9991 |
| 5) | 299 * 301 = | | 5) 300 * 300 - 1 * 1 = 89999 |
| 6) | 296 * 304 = | | 6) 300 * 300 - 4 * 4 = 89984 |
| 7) | 392 * 408 = | | 7) 400 * 400 - 8 * 8 = 159936 |
| 8) | 407 * 393 = | | 8) 400 * 400 - 7 * 7 = 159951 |
| 9) | 396 * 404 = | | 9) 400 * 400 - 4 * 4 = 159984 |
| 10) | 90 * 110 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 43 * 33 + 33 * 57 = | | 11) ( 43 + 57) * 33 = 3300 |
| 12) | 39 * 72 + 72 * 61 = | | 12) ( 61 + 39) * 72 = 7200 |
| 13) | 274 * 72 - 74 * 72 = | | 13) ( 274 - 74) * 72 = 14400 |
| 14) | 159 * 84 - 59 * 84 = | | 14) ( 159 - 59) * 84 = 8400 |
| 15) | 35 * 163 - 35 * 63 = | | 15) ( 163 - 63) * 35 = 3500 |
| 16) | 267 * 71 - 71 * 67 = | | 16) ( 267 - 67) * 71 = 14200 |
| 17) | 95 * 274 - 74 * 95 = | | 17) ( 274 - 74) * 95 = 19000 |
| 18) | 146 * 38 - 38 * 46 = | | 18) ( 146 - 46) * 38 = 3800 |
| 19) | 160 * 68 + 68 * 40 = | | 19) ( 160 + 40) * 68 = 13600 |
| 20) | 149 * 82 + 82 * 51 = | | 20) ( 149 + 51) * 82 = 16400 |
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Score: ______________ | |
