Subtract 21/40 from 7/80
7/80 - 21/40 is -7/16.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 40 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
7/80 = 7 × 1/80 × 1 = 7/80 - Likewise, for the 2nd fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Subtract the two like fractions:
7/80 - 42/80 = 7 - 42/80 = -35/80 - After reducing the fraction, the answer is -7/16
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