Answers

Subtract 8/21 from 40/81

40/81 - 8/21 is 64/567.

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,
   40/81 = 40 × 7/81 × 7 = 280/567
3. Likewise, for the 2nd fraction, since 21 × 27 = 567,
   8/21 = 8 × 27/21 × 27 = 216/567
4. Subtract the two like fractions:
   280/567 - 216/567 = 280 - 216/567 = 64/567

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