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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Friday July 24 2026
06:59:53 PM | Friday July 24 2026
06:59:53 PMFlip Answers |
| 1) | 109 * 91 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 299 * 301 = | | 2) 300 * 300 - 1 * 1 = 89999 |
| 3) | 295 * 305 = | | 3) 300 * 300 - 5 * 5 = 89975 |
| 4) | 96 * 104 = | | 4) 100 * 100 - 4 * 4 = 9984 |
| 5) | 306 * 294 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 395 * 405 = | | 6) 400 * 400 - 5 * 5 = 159975 |
| 7) | 193 * 207 = | | 7) 200 * 200 - 7 * 7 = 39951 |
| 8) | 96 * 104 = | | 8) 100 * 100 - 4 * 4 = 9984 |
| 9) | 199 * 201 = | | 9) 200 * 200 - 1 * 1 = 39999 |
| 10) | 306 * 294 = | | 10) 300 * 300 - 6 * 6 = 89964 |
| 11) | 49 * 71 + 151 * 71 = | | 11) ( 151 + 49) * 71 = 14200 |
| 12) | 147 * 54 - 47 * 54 = | | 12) ( 147 - 47) * 54 = 5400 |
| 13) | 41 * 38 + 59 * 38 = | | 13) ( 41 + 59) * 38 = 3800 |
| 14) | 272 * 78 - 72 * 78 = | | 14) ( 272 - 72) * 78 = 15600 |
| 15) | 77 * 133 + 67 * 77 = | | 15) ( 133 + 67) * 77 = 15400 |
| 16) | 56 * 23 + 44 * 23 = | | 16) ( 56 + 44) * 23 = 2300 |
| 17) | 275 * 94 - 94 * 75 = | | 17) ( 275 - 75) * 94 = 18800 |
| 18) | 71 * 64 + 71 * 136 = | | 18) ( 136 + 64) * 71 = 14200 |
| 19) | 163 * 67 - 63 * 67 = | | 19) ( 163 - 63) * 67 = 6700 |
| 20) | 41 * 80 + 80 * 159 = | | 20) ( 159 + 41) * 80 = 16000 |
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Score: ______________ | |
