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 December 24 2025
07:07:15 PM | Wednesday December 24 2025
07:07:15 PMFlip Answers |
| 1) | 99 * 101 = | | 1) 100 * 100 - 1 * 1 = 9999 |
| 2) | 291 * 309 = | | 2) 300 * 300 - 9 * 9 = 89919 |
| 3) | 398 * 402 = | | 3) 400 * 400 - 2 * 2 = 159996 |
| 4) | 396 * 404 = | | 4) 400 * 400 - 4 * 4 = 159984 |
| 5) | 294 * 306 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 204 * 196 = | | 6) 200 * 200 - 4 * 4 = 39984 |
| 7) | 398 * 402 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 107 * 93 = | | 8) 100 * 100 - 7 * 7 = 9951 |
| 9) | 91 * 109 = | | 9) 100 * 100 - 9 * 9 = 9919 |
| 10) | 402 * 398 = | | 10) 400 * 400 - 2 * 2 = 159996 |
| 11) | 243 * 69 - 43 * 69 = | | 11) ( 243 - 43) * 69 = 13800 |
| 12) | 55 * 57 + 55 * 43 = | | 12) ( 57 + 43) * 55 = 5500 |
| 13) | 262 * 61 - 62 * 61 = | | 13) ( 262 - 62) * 61 = 12200 |
| 14) | 85 * 40 + 160 * 85 = | | 14) ( 160 + 40) * 85 = 17000 |
| 15) | 77 * 39 + 61 * 77 = | | 15) ( 39 + 61) * 77 = 7700 |
| 16) | 41 * 155 + 41 * 45 = | | 16) ( 155 + 45) * 41 = 8200 |
| 17) | 125 * 41 + 75 * 41 = | | 17) ( 125 + 75) * 41 = 8200 |
| 18) | 43 * 96 + 96 * 57 = | | 18) ( 43 + 57) * 96 = 9600 |
| 19) | 24 * 269 - 69 * 24 = | | 19) ( 269 - 69) * 24 = 4800 |
| 20) | 66 * 27 + 27 * 34 = | | 20) ( 34 + 66) * 27 = 2700 |
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Score: ______________ | |
