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 May 29 2026
01:44:24 PM | Friday May 29 2026
01:44:24 PMFlip Answers |
| 1) | 310 * 290 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 110 * 90 = | | 2) 100 * 100 - 10 * 10 = 9900 |
| 3) | 396 * 404 = | | 3) 400 * 400 - 4 * 4 = 159984 |
| 4) | 99 * 101 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 398 * 402 = | | 5) 400 * 400 - 2 * 2 = 159996 |
| 6) | 95 * 105 = | | 6) 100 * 100 - 5 * 5 = 9975 |
| 7) | 203 * 197 = | | 7) 200 * 200 - 3 * 3 = 39991 |
| 8) | 105 * 95 = | | 8) 100 * 100 - 5 * 5 = 9975 |
| 9) | 299 * 301 = | | 9) 300 * 300 - 1 * 1 = 89999 |
| 10) | 294 * 306 = | | 10) 300 * 300 - 6 * 6 = 89964 |
| 11) | 258 * 46 - 46 * 58 = | | 11) ( 258 - 58) * 46 = 9200 |
| 12) | 94 * 146 - 46 * 94 = | | 12) ( 146 - 46) * 94 = 9400 |
| 13) | 138 * 59 - 59 * 38 = | | 13) ( 138 - 38) * 59 = 5900 |
| 14) | 87 * 235 - 87 * 35 = | | 14) ( 235 - 35) * 87 = 17400 |
| 15) | 25 * 146 + 54 * 25 = | | 15) ( 146 + 54) * 25 = 5000 |
| 16) | 92 * 240 - 40 * 92 = | | 16) ( 240 - 40) * 92 = 18400 |
| 17) | 94 * 158 - 58 * 94 = | | 17) ( 158 - 58) * 94 = 9400 |
| 18) | 69 * 50 + 150 * 69 = | | 18) ( 150 + 50) * 69 = 13800 |
| 19) | 47 * 40 + 60 * 47 = | | 19) ( 40 + 60) * 47 = 4700 |
| 20) | 76 * 61 + 139 * 76 = | | 20) ( 139 + 61) * 76 = 15200 |
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Score: ______________ | |
