Answers

Subtract 42/81 from 21/12

1^st number: 1 9/12, 2^nd number: 42/81

21/12 - 42/81 is 133/108.

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,
   42/81 = 42 × 4/81 × 4 = 168/324
4. Subtract the two like fractions:
   567/324 - 168/324 = 567 - 168/324 = 399/324
5. After reducing the fraction, the answer is 133/108
6. In mixed form: 125/108

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