Answers

Subtract 63/21 from 81/12

1^st number: 6 9/12, 2^nd number: 3 0/21

81/12 - 63/21 is 15/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 21 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 12 × 7 = 84,
   81/12 = 81 × 7/12 × 7 = 567/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   63/21 = 63 × 4/21 × 4 = 252/84
4. Subtract the two like fractions:
   567/84 - 252/84 = 567 - 252/84 = 315/84
5. After reducing the fraction, the answer is 15/4
6. In mixed form: 33/4

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