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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Tuesday March 17 2026
11:47:32 PM | Tuesday March 17 2026
11:47:32 PMFlip Answers |
| 1) | 397 * 403 = | | 1) 400 * 400 - 3 * 3 = 159991 |
| 2) | 305 * 295 = | | 2) 300 * 300 - 5 * 5 = 89975 |
| 3) | 297 * 303 = | | 3) 300 * 300 - 3 * 3 = 89991 |
| 4) | 103 * 97 = | | 4) 100 * 100 - 3 * 3 = 9991 |
| 5) | 294 * 306 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 96 * 104 = | | 6) 100 * 100 - 4 * 4 = 9984 |
| 7) | 302 * 298 = | | 7) 300 * 300 - 2 * 2 = 89996 |
| 8) | 198 * 202 = | | 8) 200 * 200 - 2 * 2 = 39996 |
| 9) | 209 * 191 = | | 9) 200 * 200 - 9 * 9 = 39919 |
| 10) | 301 * 299 = | | 10) 300 * 300 - 1 * 1 = 89999 |
| 11) | 60 * 30 + 40 * 30 = | | 11) ( 60 + 40) * 30 = 3000 |
| 12) | 50 * 143 + 50 * 57 = | | 12) ( 143 + 57) * 50 = 10000 |
| 13) | 60 * 73 + 127 * 60 = | | 13) ( 127 + 73) * 60 = 12000 |
| 14) | 50 * 29 + 29 * 50 = | | 14) ( 50 + 50) * 29 = 2900 |
| 15) | 256 * 66 - 66 * 56 = | | 15) ( 256 - 56) * 66 = 13200 |
| 16) | 160 * 41 + 41 * 40 = | | 16) ( 160 + 40) * 41 = 8200 |
| 17) | 256 * 21 - 21 * 56 = | | 17) ( 256 - 56) * 21 = 4200 |
| 18) | 240 * 24 - 40 * 24 = | | 18) ( 240 - 40) * 24 = 4800 |
| 19) | 40 * 91 + 91 * 160 = | | 19) ( 160 + 40) * 91 = 18200 |
| 20) | 164 * 64 - 64 * 64 = | | 20) ( 164 - 64) * 64 = 6400 |
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Score: ______________ | |
