Answers

Subtract 21/20 from 7/80

1^st number: 7/80, 2^nd number: 1 1/20

7/80 - 21/20 is -77/80.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 20 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 80 × 1 = 80,
   7/80 = 7 × 1/80 × 1 = 7/80
3. Likewise, for the 2nd fraction, since 20 × 4 = 80,
   21/20 = 21 × 4/20 × 4 = 84/80
4. Subtract the two like fractions:
   7/80 - 84/80 = 7 - 84/80 = -77/80

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