Answers

Subtract 63/4 from 21/40

1^st number: 21/40, 2^nd number: 15 3/4

21/40 - 63/4 is -609/40.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 4 is 40
   
   Next, find the equivalent fraction of both fractional numbers with denominator 40
2. For the 1st fraction, since 40 × 1 = 40,
   21/40 = 21 × 1/40 × 1 = 21/40
3. Likewise, for the 2nd fraction, since 4 × 10 = 40,
   63/4 = 63 × 10/4 × 10 = 630/40
4. Subtract the two like fractions:
   21/40 - 630/40 = 21 - 630/40 = -609/40

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