Subtract 18/54 from 21/40
21/40 - 18/54 is 23/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 54 is 1080
Next, find the equivalent fraction of both fractional numbers with denominator 1080 - For the 1st fraction, since 40 × 27 = 1080,
21/40 = 21 × 27/40 × 27 = 567/1080 - Likewise, for the 2nd fraction, since 54 × 20 = 1080,
18/54 = 18 × 20/54 × 20 = 360/1080 - Subtract the two like fractions:
567/1080 - 360/1080 = 567 - 360/1080 = 207/1080 - After reducing the fraction, the answer is 23/120
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