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 November 29 2025
05:11:39 AM | Saturday November 29 2025
05:11:39 AMFlip Answers |
| 1) | 210 * 190 = | | 1) 200 * 200 - 10 * 10 = 39900 |
| 2) | 190 * 210 = | | 2) 200 * 200 - 10 * 10 = 39900 |
| 3) | 303 * 297 = | | 3) 300 * 300 - 3 * 3 = 89991 |
| 4) | 206 * 194 = | | 4) 200 * 200 - 6 * 6 = 39964 |
| 5) | 105 * 95 = | | 5) 100 * 100 - 5 * 5 = 9975 |
| 6) | 404 * 396 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 299 * 301 = | | 7) 300 * 300 - 1 * 1 = 89999 |
| 8) | 90 * 110 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 193 * 207 = | | 9) 200 * 200 - 7 * 7 = 39951 |
| 10) | 98 * 102 = | | 10) 100 * 100 - 2 * 2 = 9996 |
| 11) | 88 * 165 + 88 * 35 = | | 11) ( 165 + 35) * 88 = 17600 |
| 12) | 144 * 68 - 68 * 44 = | | 12) ( 144 - 44) * 68 = 6800 |
| 13) | 171 * 29 - 71 * 29 = | | 13) ( 171 - 71) * 29 = 2900 |
| 14) | 43 * 32 + 157 * 32 = | | 14) ( 157 + 43) * 32 = 6400 |
| 15) | 28 * 48 + 48 * 72 = | | 15) ( 28 + 72) * 48 = 4800 |
| 16) | 57 * 151 + 57 * 49 = | | 16) ( 151 + 49) * 57 = 11400 |
| 17) | 147 * 35 - 35 * 47 = | | 17) ( 147 - 47) * 35 = 3500 |
| 18) | 53 * 41 + 53 * 59 = | | 18) ( 59 + 41) * 53 = 5300 |
| 19) | 45 * 77 + 77 * 55 = | | 19) ( 55 + 45) * 77 = 7700 |
| 20) | 83 * 252 - 52 * 83 = | | 20) ( 252 - 52) * 83 = 16600 |
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Score: ______________ | |
