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 27 2025
09:19:49 PM | Saturday December 27 2025
09:19:49 PMFlip Answers |
| 1) | 204 * 196 = | | 1) 200 * 200 - 4 * 4 = 39984 |
| 2) | 195 * 205 = | | 2) 200 * 200 - 5 * 5 = 39975 |
| 3) | 197 * 203 = | | 3) 200 * 200 - 3 * 3 = 39991 |
| 4) | 110 * 90 = | | 4) 100 * 100 - 10 * 10 = 9900 |
| 5) | 301 * 299 = | | 5) 300 * 300 - 1 * 1 = 89999 |
| 6) | 210 * 190 = | | 6) 200 * 200 - 10 * 10 = 39900 |
| 7) | 195 * 205 = | | 7) 200 * 200 - 5 * 5 = 39975 |
| 8) | 191 * 209 = | | 8) 200 * 200 - 9 * 9 = 39919 |
| 9) | 91 * 109 = | | 9) 100 * 100 - 9 * 9 = 9919 |
| 10) | 408 * 392 = | | 10) 400 * 400 - 8 * 8 = 159936 |
| 11) | 62 * 39 + 39 * 138 = | | 11) ( 138 + 62) * 39 = 7800 |
| 12) | 32 * 37 + 32 * 163 = | | 12) ( 163 + 37) * 32 = 6400 |
| 13) | 61 * 136 - 61 * 36 = | | 13) ( 136 - 36) * 61 = 6100 |
| 14) | 43 * 96 + 57 * 96 = | | 14) ( 43 + 57) * 96 = 9600 |
| 15) | 56 * 33 + 56 * 67 = | | 15) ( 33 + 67) * 56 = 5600 |
| 16) | 26 * 147 + 53 * 26 = | | 16) ( 147 + 53) * 26 = 5200 |
| 17) | 22 * 56 + 44 * 22 = | | 17) ( 44 + 56) * 22 = 2200 |
| 18) | 44 * 76 + 76 * 56 = | | 18) ( 44 + 56) * 76 = 7600 |
| 19) | 28 * 174 - 28 * 74 = | | 19) ( 174 - 74) * 28 = 2800 |
| 20) | 69 * 158 - 69 * 58 = | | 20) ( 158 - 58) * 69 = 6900 |
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Score: ______________ | |
