Answers

Subtract 21/12 from 28/72

1^st number: 28/72, 2^nd number: 1 9/12

28/72 - 21/12 is -49/36.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 12 is 72
   
   Next, find the equivalent fraction of both fractional numbers with denominator 72
2. For the 1st fraction, since 72 × 1 = 72,
   28/72 = 28 × 1/72 × 1 = 28/72
3. Likewise, for the 2nd fraction, since 12 × 6 = 72,
   21/12 = 21 × 6/12 × 6 = 126/72
4. Subtract the two like fractions:
   28/72 - 126/72 = 28 - 126/72 = -98/72
5. After reducing the fraction, the answer is -49/36

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