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 August 30 2026
08:39:09 AM | Sunday August 30 2026
08:39:09 AMFlip Answers |
| 1) | 395 * 405 = | | 1) 400 * 400 - 5 * 5 = 159975 |
| 2) | 107 * 93 = | | 2) 100 * 100 - 7 * 7 = 9951 |
| 3) | 301 * 299 = | | 3) 300 * 300 - 1 * 1 = 89999 |
| 4) | 394 * 406 = | | 4) 400 * 400 - 6 * 6 = 159964 |
| 5) | 307 * 293 = | | 5) 300 * 300 - 7 * 7 = 89951 |
| 6) | 305 * 295 = | | 6) 300 * 300 - 5 * 5 = 89975 |
| 7) | 196 * 204 = | | 7) 200 * 200 - 4 * 4 = 39984 |
| 8) | 109 * 91 = | | 8) 100 * 100 - 9 * 9 = 9919 |
| 9) | 210 * 190 = | | 9) 200 * 200 - 10 * 10 = 39900 |
| 10) | 195 * 205 = | | 10) 200 * 200 - 5 * 5 = 39975 |
| 11) | 169 * 97 - 69 * 97 = | | 11) ( 169 - 69) * 97 = 9700 |
| 12) | 52 * 23 + 48 * 23 = | | 12) ( 52 + 48) * 23 = 2300 |
| 13) | 165 * 57 + 57 * 35 = | | 13) ( 165 + 35) * 57 = 11400 |
| 14) | 27 * 263 - 27 * 63 = | | 14) ( 263 - 63) * 27 = 5400 |
| 15) | 242 * 51 - 51 * 42 = | | 15) ( 242 - 42) * 51 = 10200 |
| 16) | 28 * 160 - 60 * 28 = | | 16) ( 160 - 60) * 28 = 2800 |
| 17) | 77 * 167 - 77 * 67 = | | 17) ( 167 - 67) * 77 = 7700 |
| 18) | 67 * 158 - 58 * 67 = | | 18) ( 158 - 58) * 67 = 6700 |
| 19) | 70 * 23 + 23 * 130 = | | 19) ( 130 + 70) * 23 = 4600 |
| 20) | 261 * 36 - 36 * 61 = | | 20) ( 261 - 61) * 36 = 7200 |
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Score: ______________ | |
