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 July 27 2026
12:38:12 AM | Monday July 27 2026
12:38:12 AMFlip Answers |
| 1) | 199 * 201 = | | 1) 200 * 200 - 1 * 1 = 39999 |
| 2) | 404 * 396 = | | 2) 400 * 400 - 4 * 4 = 159984 |
| 3) | 96 * 104 = | | 3) 100 * 100 - 4 * 4 = 9984 |
| 4) | 390 * 410 = | | 4) 400 * 400 - 10 * 10 = 159900 |
| 5) | 307 * 293 = | | 5) 300 * 300 - 7 * 7 = 89951 |
| 6) | 91 * 109 = | | 6) 100 * 100 - 9 * 9 = 9919 |
| 7) | 406 * 394 = | | 7) 400 * 400 - 6 * 6 = 159964 |
| 8) | 293 * 307 = | | 8) 300 * 300 - 7 * 7 = 89951 |
| 9) | 301 * 299 = | | 9) 300 * 300 - 1 * 1 = 89999 |
| 10) | 399 * 401 = | | 10) 400 * 400 - 1 * 1 = 159999 |
| 11) | 138 * 93 - 38 * 93 = | | 11) ( 138 - 38) * 93 = 9300 |
| 12) | 45 * 60 + 60 * 55 = | | 12) ( 55 + 45) * 60 = 6000 |
| 13) | 74 * 48 + 74 * 52 = | | 13) ( 48 + 52) * 74 = 7400 |
| 14) | 135 * 58 + 58 * 65 = | | 14) ( 135 + 65) * 58 = 11600 |
| 15) | 70 * 168 - 68 * 70 = | | 15) ( 168 - 68) * 70 = 7000 |
| 16) | 57 * 57 + 57 * 43 = | | 16) ( 43 + 57) * 57 = 5700 |
| 17) | 82 * 148 - 48 * 82 = | | 17) ( 148 - 48) * 82 = 8200 |
| 18) | 153 * 87 + 47 * 87 = | | 18) ( 153 + 47) * 87 = 17400 |
| 19) | 90 * 149 - 49 * 90 = | | 19) ( 149 - 49) * 90 = 9000 |
| 20) | 59 * 161 + 59 * 39 = | | 20) ( 161 + 39) * 59 = 11800 |
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Score: ______________ | |
