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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Saturday December 13 2025
02:56:53 PM | Saturday December 13 2025
02:56:53 PMFlip Answers |
| 1) | 206 * 194 = | | 1) 200 * 200 - 6 * 6 = 39964 |
| 2) | 90 * 110 = | | 2) 100 * 100 - 10 * 10 = 9900 |
| 3) | 99 * 101 = | | 3) 100 * 100 - 1 * 1 = 9999 |
| 4) | 402 * 398 = | | 4) 400 * 400 - 2 * 2 = 159996 |
| 5) | 96 * 104 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 309 * 291 = | | 6) 300 * 300 - 9 * 9 = 89919 |
| 7) | 106 * 94 = | | 7) 100 * 100 - 6 * 6 = 9964 |
| 8) | 298 * 302 = | | 8) 300 * 300 - 2 * 2 = 89996 |
| 9) | 404 * 396 = | | 9) 400 * 400 - 4 * 4 = 159984 |
| 10) | 209 * 191 = | | 10) 200 * 200 - 9 * 9 = 39919 |
| 11) | 91 * 160 - 91 * 60 = | | 11) ( 160 - 60) * 91 = 9100 |
| 12) | 91 * 38 + 62 * 91 = | | 12) ( 62 + 38) * 91 = 9100 |
| 13) | 73 * 90 + 90 * 27 = | | 13) ( 27 + 73) * 90 = 9000 |
| 14) | 68 * 154 + 68 * 46 = | | 14) ( 154 + 46) * 68 = 13600 |
| 15) | 73 * 28 + 28 * 27 = | | 15) ( 27 + 73) * 28 = 2800 |
| 16) | 68 * 62 + 62 * 132 = | | 16) ( 132 + 68) * 62 = 12400 |
| 17) | 133 * 32 + 67 * 32 = | | 17) ( 133 + 67) * 32 = 6400 |
| 18) | 78 * 66 + 78 * 134 = | | 18) ( 134 + 66) * 78 = 15600 |
| 19) | 75 * 97 + 25 * 97 = | | 19) ( 25 + 75) * 97 = 9700 |
| 20) | 37 * 39 + 61 * 37 = | | 20) ( 61 + 39) * 37 = 3700 |
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Score: ______________ | |
