Answers

Subtract 72/10 from 21/30

1^st number: 21/30, 2^nd number: 7 2/10

21/30 - 72/10 is -13/2.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 10 is 30
   
   Next, find the equivalent fraction of both fractional numbers with denominator 30
2. For the 1st fraction, since 30 × 1 = 30,
   21/30 = 21 × 1/30 × 1 = 21/30
3. Likewise, for the 2nd fraction, since 10 × 3 = 30,
   72/10 = 72 × 3/10 × 3 = 216/30
4. Subtract the two like fractions:
   21/30 - 216/30 = 21 - 216/30 = -195/30
5. After reducing the fraction, the answer is -13/2

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