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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Friday October 09 2026
03:30:29 PM | Friday October 09 2026
03:30:29 PMFlip Answers |
| 1) | 195 * 205 = | | 1) 200 * 200 - 5 * 5 = 39975 |
| 2) | 196 * 204 = | | 2) 200 * 200 - 4 * 4 = 39984 |
| 3) | 198 * 202 = | | 3) 200 * 200 - 2 * 2 = 39996 |
| 4) | 393 * 407 = | | 4) 400 * 400 - 7 * 7 = 159951 |
| 5) | 410 * 390 = | | 5) 400 * 400 - 10 * 10 = 159900 |
| 6) | 108 * 92 = | | 6) 100 * 100 - 8 * 8 = 9936 |
| 7) | 303 * 297 = | | 7) 300 * 300 - 3 * 3 = 89991 |
| 8) | 393 * 407 = | | 8) 400 * 400 - 7 * 7 = 159951 |
| 9) | 204 * 196 = | | 9) 200 * 200 - 4 * 4 = 39984 |
| 10) | 203 * 197 = | | 10) 200 * 200 - 3 * 3 = 39991 |
| 11) | 24 * 60 + 24 * 40 = | | 11) ( 40 + 60) * 24 = 2400 |
| 12) | 45 * 268 - 45 * 68 = | | 12) ( 268 - 68) * 45 = 9000 |
| 13) | 275 * 75 - 75 * 75 = | | 13) ( 275 - 75) * 75 = 15000 |
| 14) | 66 * 32 + 34 * 32 = | | 14) ( 34 + 66) * 32 = 3200 |
| 15) | 65 * 50 + 65 * 50 = | | 15) ( 50 + 50) * 65 = 6500 |
| 16) | 60 * 69 + 69 * 40 = | | 16) ( 40 + 60) * 69 = 6900 |
| 17) | 47 * 66 + 66 * 53 = | | 17) ( 53 + 47) * 66 = 6600 |
| 18) | 168 * 47 - 68 * 47 = | | 18) ( 168 - 68) * 47 = 4700 |
| 19) | 161 * 94 - 94 * 61 = | | 19) ( 161 - 61) * 94 = 9400 |
| 20) | 63 * 53 + 53 * 37 = | | 20) ( 63 + 37) * 53 = 5300 |
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Score: ______________ | |
