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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Sunday June 28 2026
03:42:19 PM | Sunday June 28 2026
03:42:19 PMFlip Answers |
| 1) | 202 * 198 = | | 1) 200 * 200 - 2 * 2 = 39996 |
| 2) | 190 * 210 = | | 2) 200 * 200 - 10 * 10 = 39900 |
| 3) | 290 * 310 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 301 * 299 = | | 4) 300 * 300 - 1 * 1 = 89999 |
| 5) | 402 * 398 = | | 5) 400 * 400 - 2 * 2 = 159996 |
| 6) | 397 * 403 = | | 6) 400 * 400 - 3 * 3 = 159991 |
| 7) | 404 * 396 = | | 7) 400 * 400 - 4 * 4 = 159984 |
| 8) | 308 * 292 = | | 8) 300 * 300 - 8 * 8 = 89936 |
| 9) | 295 * 305 = | | 9) 300 * 300 - 5 * 5 = 89975 |
| 10) | 196 * 204 = | | 10) 200 * 200 - 4 * 4 = 39984 |
| 11) | 82 * 136 + 82 * 64 = | | 11) ( 136 + 64) * 82 = 16400 |
| 12) | 136 * 21 + 21 * 64 = | | 12) ( 136 + 64) * 21 = 4200 |
| 13) | 60 * 21 + 21 * 140 = | | 13) ( 140 + 60) * 21 = 4200 |
| 14) | 165 * 36 - 65 * 36 = | | 14) ( 165 - 65) * 36 = 3600 |
| 15) | 36 * 171 - 36 * 71 = | | 15) ( 171 - 71) * 36 = 3600 |
| 16) | 146 * 70 - 46 * 70 = | | 16) ( 146 - 46) * 70 = 7000 |
| 17) | 53 * 70 + 53 * 30 = | | 17) ( 30 + 70) * 53 = 5300 |
| 18) | 27 * 247 - 27 * 47 = | | 18) ( 247 - 47) * 27 = 5400 |
| 19) | 37 * 47 + 53 * 37 = | | 19) ( 53 + 47) * 37 = 3700 |
| 20) | 244 * 54 - 44 * 54 = | | 20) ( 244 - 44) * 54 = 10800 |
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Score: ______________ | |
