Subtract 7/40 from 21/54
21/54 - 7/40 is 77/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 40 is 1080
Next, find the equivalent fraction of both fractional numbers with denominator 1080 - For the 1st fraction, since 54 × 20 = 1080,
21/54 = 21 × 20/54 × 20 = 420/1080 - Likewise, for the 2nd fraction, since 40 × 27 = 1080,
7/40 = 7 × 27/40 × 27 = 189/1080 - Subtract the two like fractions:
420/1080 - 189/1080 = 420 - 189/1080 = 231/1080 - After reducing the fraction, the answer is 77/360
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