Answers

Subtract 15/63 from 20/42

20/42 - 15/63 is 5/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 63 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 42 × 3 = 126,
   20/42 = 20 × 3/42 × 3 = 60/126
3. Likewise, for the 2nd fraction, since 63 × 2 = 126,
   15/63 = 15 × 2/63 × 2 = 30/126
4. Subtract the two like fractions:
   60/126 - 30/126 = 60 - 30/126 = 30/126
5. After reducing the fraction, the answer is 5/21

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