Answers

Subtract 15/80 from 21/20

1^st number: 1 1/20, 2^nd number: 15/80

21/20 - 15/80 is 69/80.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 80 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 20 × 4 = 80,
   21/20 = 21 × 4/20 × 4 = 84/80
3. Likewise, for the 2nd fraction, since 80 × 1 = 80,
   15/80 = 15 × 1/80 × 1 = 15/80
4. Subtract the two like fractions:
   84/80 - 15/80 = 84 - 15/80 = 69/80

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