Subtract 21/27 from 28/40
28/40 - 21/27 is -7/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 27 is 1080
Next, find the equivalent fraction of both fractional numbers with denominator 1080 - For the 1st fraction, since 40 × 27 = 1080,
28/40 = 28 × 27/40 × 27 = 756/1080 - Likewise, for the 2nd fraction, since 27 × 40 = 1080,
21/27 = 21 × 40/27 × 40 = 840/1080 - Subtract the two like fractions:
756/1080 - 840/1080 = 756 - 840/1080 = -84/1080 - After reducing the fraction, the answer is -7/90
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