Answers

Subtract 84/81 from 8/21

1^st number: 8/21, 2^nd number: 1 3/81

8/21 - 84/81 is -124/189.

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,
   8/21 = 8 × 27/21 × 27 = 216/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   84/81 = 84 × 7/81 × 7 = 588/567
4. Subtract the two like fractions:
   216/567 - 588/567 = 216 - 588/567 = -372/567
5. After reducing the fraction, the answer is -124/189

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