Subtract 21/40 from 35/80
35/80 - 21/40 is -7/80.
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,
35/80 = 35 × 1/80 × 1 = 35/80 - Likewise, for the 2nd fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Subtract the two like fractions:
35/80 - 42/80 = 35 - 42/80 = -7/80
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