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 November 26 2025 10:31:19 PM | Wednesday November 26 2025 10:31:19 PMFlip Answers |
| 1) | 310 * 290 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 92 * 108 = | | 2) 100 * 100 - 8 * 8 = 9936 |
| 3) | 207 * 193 = | | 3) 200 * 200 - 7 * 7 = 39951 |
| 4) | 390 * 410 = | | 4) 400 * 400 - 10 * 10 = 159900 |
| 5) | 210 * 190 = | | 5) 200 * 200 - 10 * 10 = 39900 |
| 6) | 404 * 396 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 298 * 302 = | | 7) 300 * 300 - 2 * 2 = 89996 |
| 8) | 92 * 108 = | | 8) 100 * 100 - 8 * 8 = 9936 |
| 9) | 306 * 294 = | | 9) 300 * 300 - 6 * 6 = 89964 |
| 10) | 105 * 95 = | | 10) 100 * 100 - 5 * 5 = 9975 |
| 11) | 51 * 45 + 149 * 45 = | | 11) ( 149 + 51) * 45 = 9000 |
| 12) | 52 * 23 + 23 * 48 = | | 12) ( 52 + 48) * 23 = 2300 |
| 13) | 265 * 39 - 65 * 39 = | | 13) ( 265 - 65) * 39 = 7800 |
| 14) | 24 * 48 + 152 * 24 = | | 14) ( 152 + 48) * 24 = 4800 |
| 15) | 46 * 25 + 46 * 75 = | | 15) ( 25 + 75) * 46 = 4600 |
| 16) | 75 * 262 - 62 * 75 = | | 16) ( 262 - 62) * 75 = 15000 |
| 17) | 60 * 161 + 60 * 39 = | | 17) ( 161 + 39) * 60 = 12000 |
| 18) | 70 * 145 - 70 * 45 = | | 18) ( 145 - 45) * 70 = 7000 |
| 19) | 52 * 33 + 67 * 52 = | | 19) ( 33 + 67) * 52 = 5200 |
| 20) | 79 * 40 + 60 * 79 = | | 20) ( 40 + 60) * 79 = 7900 |
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Score: ______________ | |