Answers

Subtract 21/16 from 21/40

1^st number: 21/40, 2^nd number: 1 5/16

21/40 - 21/16 is -63/80.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 16 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 40 × 2 = 80,
   21/40 = 21 × 2/40 × 2 = 42/80
3. Likewise, for the 2nd fraction, since 16 × 5 = 80,
   21/16 = 21 × 5/16 × 5 = 105/80
4. Subtract the two like fractions:
   42/80 - 105/80 = 42 - 105/80 = -63/80

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