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 December 05 2025
03:27:19 PM | Friday December 05 2025
03:27:19 PMFlip Answers |
| 1) | 209 * 191 = | | 1) 200 * 200 - 9 * 9 = 39919 |
| 2) | 408 * 392 = | | 2) 400 * 400 - 8 * 8 = 159936 |
| 3) | 301 * 299 = | | 3) 300 * 300 - 1 * 1 = 89999 |
| 4) | 402 * 398 = | | 4) 400 * 400 - 2 * 2 = 159996 |
| 5) | 101 * 99 = | | 5) 100 * 100 - 1 * 1 = 9999 |
| 6) | 201 * 199 = | | 6) 200 * 200 - 1 * 1 = 39999 |
| 7) | 402 * 398 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 195 * 205 = | | 8) 200 * 200 - 5 * 5 = 39975 |
| 9) | 410 * 390 = | | 9) 400 * 400 - 10 * 10 = 159900 |
| 10) | 292 * 308 = | | 10) 300 * 300 - 8 * 8 = 89936 |
| 11) | 44 * 89 + 89 * 56 = | | 11) ( 56 + 44) * 89 = 8900 |
| 12) | 274 * 30 - 74 * 30 = | | 12) ( 274 - 74) * 30 = 6000 |
| 13) | 56 * 73 + 127 * 56 = | | 13) ( 127 + 73) * 56 = 11200 |
| 14) | 44 * 66 + 44 * 34 = | | 14) ( 34 + 66) * 44 = 4400 |
| 15) | 41 * 125 + 41 * 75 = | | 15) ( 125 + 75) * 41 = 8200 |
| 16) | 275 * 69 - 69 * 75 = | | 16) ( 275 - 75) * 69 = 13800 |
| 17) | 271 * 58 - 58 * 71 = | | 17) ( 271 - 71) * 58 = 11600 |
| 18) | 83 * 37 + 163 * 83 = | | 18) ( 163 + 37) * 83 = 16600 |
| 19) | 93 * 36 + 64 * 93 = | | 19) ( 36 + 64) * 93 = 9300 |
| 20) | 26 * 49 + 49 * 74 = | | 20) ( 26 + 74) * 49 = 4900 |
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Score: ______________ | |
