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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Wednesday July 22 2026
06:00:54 PM | Wednesday July 22 2026
06:00:54 PMFlip Answers |
| 1) | 196 * 204 = | | 1) 200 * 200 - 4 * 4 = 39984 |
| 2) | 210 * 190 = | | 2) 200 * 200 - 10 * 10 = 39900 |
| 3) | 410 * 390 = | | 3) 400 * 400 - 10 * 10 = 159900 |
| 4) | 205 * 195 = | | 4) 200 * 200 - 5 * 5 = 39975 |
| 5) | 203 * 197 = | | 5) 200 * 200 - 3 * 3 = 39991 |
| 6) | 199 * 201 = | | 6) 200 * 200 - 1 * 1 = 39999 |
| 7) | 297 * 303 = | | 7) 300 * 300 - 3 * 3 = 89991 |
| 8) | 391 * 409 = | | 8) 400 * 400 - 9 * 9 = 159919 |
| 9) | 204 * 196 = | | 9) 200 * 200 - 4 * 4 = 39984 |
| 10) | 99 * 101 = | | 10) 100 * 100 - 1 * 1 = 9999 |
| 11) | 161 * 49 - 61 * 49 = | | 11) ( 161 - 61) * 49 = 4900 |
| 12) | 65 * 244 - 44 * 65 = | | 12) ( 244 - 44) * 65 = 13000 |
| 13) | 51 * 72 + 51 * 128 = | | 13) ( 128 + 72) * 51 = 10200 |
| 14) | 162 * 38 - 38 * 62 = | | 14) ( 162 - 62) * 38 = 3800 |
| 15) | 68 * 135 - 68 * 35 = | | 15) ( 135 - 35) * 68 = 6800 |
| 16) | 46 * 250 - 50 * 46 = | | 16) ( 250 - 50) * 46 = 9200 |
| 17) | 145 * 93 + 93 * 55 = | | 17) ( 145 + 55) * 93 = 18600 |
| 18) | 82 * 145 + 55 * 82 = | | 18) ( 145 + 55) * 82 = 16400 |
| 19) | 163 * 54 + 37 * 54 = | | 19) ( 163 + 37) * 54 = 10800 |
| 20) | 158 * 54 + 54 * 42 = | | 20) ( 158 + 42) * 54 = 10800 |
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Score: ______________ | |
