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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Sunday May 03 2026
04:20:14 AM | Sunday May 03 2026
04:20:14 AMFlip Answers |
| 1) | 210 * 190 = | | 1) 200 * 200 - 10 * 10 = 39900 |
| 2) | 398 * 402 = | | 2) 400 * 400 - 2 * 2 = 159996 |
| 3) | 103 * 97 = | | 3) 100 * 100 - 3 * 3 = 9991 |
| 4) | 210 * 190 = | | 4) 200 * 200 - 10 * 10 = 39900 |
| 5) | 203 * 197 = | | 5) 200 * 200 - 3 * 3 = 39991 |
| 6) | 294 * 306 = | | 6) 300 * 300 - 6 * 6 = 89964 |
| 7) | 102 * 98 = | | 7) 100 * 100 - 2 * 2 = 9996 |
| 8) | 99 * 101 = | | 8) 100 * 100 - 1 * 1 = 9999 |
| 9) | 96 * 104 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 98 * 102 = | | 10) 100 * 100 - 2 * 2 = 9996 |
| 11) | 138 * 28 - 38 * 28 = | | 11) ( 138 - 38) * 28 = 2800 |
| 12) | 143 * 88 + 57 * 88 = | | 12) ( 143 + 57) * 88 = 17600 |
| 13) | 46 * 49 + 154 * 49 = | | 13) ( 154 + 46) * 49 = 9800 |
| 14) | 62 * 49 + 62 * 151 = | | 14) ( 151 + 49) * 62 = 12400 |
| 15) | 65 * 77 + 135 * 77 = | | 15) ( 135 + 65) * 77 = 15400 |
| 16) | 72 * 260 - 60 * 72 = | | 16) ( 260 - 60) * 72 = 14400 |
| 17) | 91 * 264 - 91 * 64 = | | 17) ( 264 - 64) * 91 = 18200 |
| 18) | 85 * 41 + 59 * 85 = | | 18) ( 59 + 41) * 85 = 8500 |
| 19) | 34 * 61 + 34 * 139 = | | 19) ( 139 + 61) * 34 = 6800 |
| 20) | 38 * 49 + 49 * 162 = | | 20) ( 162 + 38) * 49 = 9800 |
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Score: ______________ | |
