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 June 10 2026
11:21:48 PM | Wednesday June 10 2026
11:21:48 PMFlip Answers |
| 1) | 406 * 394 = | | 1) 400 * 400 - 6 * 6 = 159964 |
| 2) | 190 * 210 = | | 2) 200 * 200 - 10 * 10 = 39900 |
| 3) | 397 * 403 = | | 3) 400 * 400 - 3 * 3 = 159991 |
| 4) | 407 * 393 = | | 4) 400 * 400 - 7 * 7 = 159951 |
| 5) | 299 * 301 = | | 5) 300 * 300 - 1 * 1 = 89999 |
| 6) | 293 * 307 = | | 6) 300 * 300 - 7 * 7 = 89951 |
| 7) | 295 * 305 = | | 7) 300 * 300 - 5 * 5 = 89975 |
| 8) | 101 * 99 = | | 8) 100 * 100 - 1 * 1 = 9999 |
| 9) | 309 * 291 = | | 9) 300 * 300 - 9 * 9 = 89919 |
| 10) | 407 * 393 = | | 10) 400 * 400 - 7 * 7 = 159951 |
| 11) | 266 * 69 - 69 * 66 = | | 11) ( 266 - 66) * 69 = 13800 |
| 12) | 94 * 166 - 94 * 66 = | | 12) ( 166 - 66) * 94 = 9400 |
| 13) | 39 * 45 + 45 * 61 = | | 13) ( 39 + 61) * 45 = 4500 |
| 14) | 65 * 40 + 40 * 35 = | | 14) ( 35 + 65) * 40 = 4000 |
| 15) | 142 * 43 - 43 * 42 = | | 15) ( 142 - 42) * 43 = 4300 |
| 16) | 137 * 48 - 48 * 37 = | | 16) ( 137 - 37) * 48 = 4800 |
| 17) | 72 * 52 + 52 * 128 = | | 17) ( 128 + 72) * 52 = 10400 |
| 18) | 161 * 37 + 37 * 39 = | | 18) ( 161 + 39) * 37 = 7400 |
| 19) | 235 * 80 - 80 * 35 = | | 19) ( 235 - 35) * 80 = 16000 |
| 20) | 24 * 236 - 36 * 24 = | | 20) ( 236 - 36) * 24 = 4800 |
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Score: ______________ | |
