Answers

Subtract 21/5 from 21/80

1^st number: 21/80, 2^nd number: 4 1/5

21/80 - 21/5 is -63/16.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 5 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 80 × 1 = 80,
   21/80 = 21 × 1/80 × 1 = 21/80
3. Likewise, for the 2nd fraction, since 5 × 16 = 80,
   21/5 = 21 × 16/5 × 16 = 336/80
4. Subtract the two like fractions:
   21/80 - 336/80 = 21 - 336/80 = -315/80
5. After reducing the fraction, the answer is -63/16

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