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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Tuesday May 19 2026
01:39:33 AM | Tuesday May 19 2026
01:39:33 AMFlip Answers |
| 1) | 394 * 406 = | | 1) 400 * 400 - 6 * 6 = 159964 |
| 2) | 390 * 410 = | | 2) 400 * 400 - 10 * 10 = 159900 |
| 3) | 108 * 92 = | | 3) 100 * 100 - 8 * 8 = 9936 |
| 4) | 391 * 409 = | | 4) 400 * 400 - 9 * 9 = 159919 |
| 5) | 403 * 397 = | | 5) 400 * 400 - 3 * 3 = 159991 |
| 6) | 105 * 95 = | | 6) 100 * 100 - 5 * 5 = 9975 |
| 7) | 303 * 297 = | | 7) 300 * 300 - 3 * 3 = 89991 |
| 8) | 96 * 104 = | | 8) 100 * 100 - 4 * 4 = 9984 |
| 9) | 410 * 390 = | | 9) 400 * 400 - 10 * 10 = 159900 |
| 10) | 110 * 90 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 53 * 149 - 49 * 53 = | | 11) ( 149 - 49) * 53 = 5300 |
| 12) | 57 * 257 - 57 * 57 = | | 12) ( 257 - 57) * 57 = 11400 |
| 13) | 74 * 130 + 74 * 70 = | | 13) ( 130 + 70) * 74 = 14800 |
| 14) | 33 * 73 + 73 * 67 = | | 14) ( 33 + 67) * 73 = 7300 |
| 15) | 93 * 161 + 39 * 93 = | | 15) ( 161 + 39) * 93 = 18600 |
| 16) | 57 * 249 - 57 * 49 = | | 16) ( 249 - 49) * 57 = 11400 |
| 17) | 139 * 75 - 75 * 39 = | | 17) ( 139 - 39) * 75 = 7500 |
| 18) | 137 * 85 - 85 * 37 = | | 18) ( 137 - 37) * 85 = 8500 |
| 19) | 50 * 67 + 67 * 150 = | | 19) ( 150 + 50) * 67 = 13400 |
| 20) | 129 * 38 + 71 * 38 = | | 20) ( 129 + 71) * 38 = 7600 |
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Score: ______________ | |
