Subtract 42/54 from 28/40
28/40 - 42/54 is -7/90.
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,
28/40 = 28 × 27/40 × 27 = 756/1080 - Likewise, for the 2nd fraction, since 54 × 20 = 1080,
42/54 = 42 × 20/54 × 20 = 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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