Answers

Subtract 15/7 from 21/5

1^st number: 4 1/5, 2^nd number: 2 1/7

21/5 - 15/7 is 72/35.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 5 and 7 is 35
   
   Next, find the equivalent fraction of both fractional numbers with denominator 35
2. For the 1st fraction, since 5 × 7 = 35,
   21/5 = 21 × 7/5 × 7 = 147/35
3. Likewise, for the 2nd fraction, since 7 × 5 = 35,
   15/7 = 15 × 5/7 × 5 = 75/35
4. Subtract the two like fractions:
   147/35 - 75/35 = 147 - 75/35 = 72/35
5. In mixed form: 22/35

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