Answers

Subtract 4/81 from 5/21

5/21 - 4/81 is 107/567.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   5/21 = 5 × 27/21 × 27 = 135/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   4/81 = 4 × 7/81 × 7 = 28/567
4. Subtract the two like fractions:
   135/567 - 28/567 = 135 - 28/567 = 107/567

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