Answers

Subtract 21/81 from 28/21

1^st number: 1 7/21, 2^nd number: 21/81

28/21 - 21/81 is 29/27.

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,
   28/21 = 28 × 27/21 × 27 = 756/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   21/81 = 21 × 7/81 × 7 = 147/567
4. Subtract the two like fractions:
   756/567 - 147/567 = 756 - 147/567 = 609/567
5. After reducing the fraction, the answer is 29/27
6. In mixed form: 12/27

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