Subtract 21/40 from 2/5
2/5 - 21/40 is -1/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
2/5 = 2 × 8/5 × 8 = 16/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Subtract the two like fractions:
16/40 - 21/40 = 16 - 21/40 = -5/40 - After reducing the fraction, the answer is -1/8
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