Answers

Subtract 2/81 from 21/30

21/30 - 2/81 is 547/810.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 30 × 27 = 810,
   21/30 = 21 × 27/30 × 27 = 567/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   2/81 = 2 × 10/81 × 10 = 20/810
4. Subtract the two like fractions:
   567/810 - 20/810 = 567 - 20/810 = 547/810

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