Subtract 21/80 from 28/20
1st number: 1 8/20, 2nd number: 21/80
28/20 - 21/80 is 91/80.
Steps for subtracting fractions
- 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 - For the 1st fraction, since 20 × 4 = 80,
28/20 = 28 × 4/20 × 4 = 112/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Subtract the two like fractions:
112/80 - 21/80 = 112 - 21/80 = 91/80 - In mixed form: 111/80
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