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 18 2026
12:06:48 AM | Monday May 18 2026
12:06:48 AMFlip Answers |
| 1) | 99 * 101 = | | 1) 100 * 100 - 1 * 1 = 9999 |
| 2) | 98 * 102 = | | 2) 100 * 100 - 2 * 2 = 9996 |
| 3) | 93 * 107 = | | 3) 100 * 100 - 7 * 7 = 9951 |
| 4) | 408 * 392 = | | 4) 400 * 400 - 8 * 8 = 159936 |
| 5) | 90 * 110 = | | 5) 100 * 100 - 10 * 10 = 9900 |
| 6) | 210 * 190 = | | 6) 200 * 200 - 10 * 10 = 39900 |
| 7) | 204 * 196 = | | 7) 200 * 200 - 4 * 4 = 39984 |
| 8) | 192 * 208 = | | 8) 200 * 200 - 8 * 8 = 39936 |
| 9) | 304 * 296 = | | 9) 300 * 300 - 4 * 4 = 89984 |
| 10) | 394 * 406 = | | 10) 400 * 400 - 6 * 6 = 159964 |
| 11) | 260 * 69 - 60 * 69 = | | 11) ( 260 - 60) * 69 = 13800 |
| 12) | 47 * 77 + 53 * 77 = | | 12) ( 53 + 47) * 77 = 7700 |
| 13) | 47 * 53 + 47 * 47 = | | 13) ( 53 + 47) * 47 = 4700 |
| 14) | 69 * 135 - 35 * 69 = | | 14) ( 135 - 35) * 69 = 6900 |
| 15) | 83 * 39 + 83 * 61 = | | 15) ( 61 + 39) * 83 = 8300 |
| 16) | 83 * 243 - 43 * 83 = | | 16) ( 243 - 43) * 83 = 16600 |
| 17) | 43 * 61 + 57 * 61 = | | 17) ( 43 + 57) * 61 = 6100 |
| 18) | 171 * 37 - 37 * 71 = | | 18) ( 171 - 71) * 37 = 3700 |
| 19) | 263 * 23 - 63 * 23 = | | 19) ( 263 - 63) * 23 = 4600 |
| 20) | 43 * 93 + 57 * 93 = | | 20) ( 57 + 43) * 93 = 9300 |
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Score: ______________ | |
