Subtract 21/40 from 4/5
4/5 - 21/40 is 11/40.
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,
4/5 = 4 × 8/5 × 8 = 32/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Subtract the two like fractions:
32/40 - 21/40 = 32 - 21/40 = 11/40
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