Answers

Subtract 75/81 from 18/84

18/84 - 75/81 is -269/378.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 81 is 2268
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2268
2. For the 1st fraction, since 84 × 27 = 2268,
   18/84 = 18 × 27/84 × 27 = 486/2268
3. Likewise, for the 2nd fraction, since 81 × 28 = 2268,
   75/81 = 75 × 28/81 × 28 = 2100/2268
4. Subtract the two like fractions:
   486/2268 - 2100/2268 = 486 - 2100/2268 = -1614/2268
5. After reducing the fraction, the answer is -269/378

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