Answers

Subtract 1/21 from 2/81

2/81 - 1/21 is -13/567.

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,
   2/81 = 2 × 7/81 × 7 = 14/567
3. Likewise, for the 2nd fraction, since 21 × 27 = 567,
   1/21 = 1 × 27/21 × 27 = 27/567
4. Subtract the two like fractions:
   14/567 - 27/567 = 14 - 27/567 = -13/567

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