Answers

Subtract 15/12 from 8/21

1^st number: 8/21, 2^nd number: 1 3/12

8/21 - 15/12 is -73/84.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 12 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   8/21 = 8 × 4/21 × 4 = 32/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   15/12 = 15 × 7/12 × 7 = 105/84
4. Subtract the two like fractions:
   32/84 - 105/84 = 32 - 105/84 = -73/84

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