Answers

Subtract 5/21 from 6/81

6/81 - 5/21 is -31/189.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 21 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 81 × 7 = 567,
   6/81 = 6 × 7/81 × 7 = 42/567
3. Likewise, for the 2nd fraction, since 21 × 27 = 567,
   5/21 = 5 × 27/21 × 27 = 135/567
4. Subtract the two like fractions:
   42/567 - 135/567 = 42 - 135/567 = -93/567
5. After reducing the fraction, the answer is -31/189

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