Answers

Subtract 80/81 from 21/12

1^st number: 1 9/12, 2^nd number: 80/81

21/12 - 80/81 is 247/324.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 81 is 324
   
   Next, find the equivalent fraction of both fractional numbers with denominator 324
2. For the 1st fraction, since 12 × 27 = 324,
   21/12 = 21 × 27/12 × 27 = 567/324
3. Likewise, for the 2nd fraction, since 81 × 4 = 324,
   80/81 = 80 × 4/81 × 4 = 320/324
4. Subtract the two like fractions:
   567/324 - 320/324 = 567 - 320/324 = 247/324

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