Subtract 7/20 from 21/80
21/80 - 7/20 is -7/80.
Steps for subtracting fractions
- 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 - For the 1st fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Likewise, for the 2nd fraction, since 20 × 4 = 80,
7/20 = 7 × 4/20 × 4 = 28/80 - Subtract the two like fractions:
21/80 - 28/80 = 21 - 28/80 = -7/80
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