Subtract 5/8 from 21/40
21/40 - 5/8 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
5/8 = 5 × 5/8 × 5 = 25/40 - Subtract the two like fractions:
21/40 - 25/40 = 21 - 25/40 = -4/40 - After reducing the fraction, the answer is -1/10
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