Answers

Subtract 49/81 from 9/21

9/21 - 49/81 is -100/567.

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,
   9/21 = 9 × 27/21 × 27 = 243/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   49/81 = 49 × 7/81 × 7 = 343/567
4. Subtract the two like fractions:
   243/567 - 343/567 = 243 - 343/567 = -100/567

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