Subtract 27/28 from 18/40
18/40 - 27/28 is -18/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 28 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
18/40 = 18 × 7/40 × 7 = 126/280 - Likewise, for the 2nd fraction, since 28 × 10 = 280,
27/28 = 27 × 10/28 × 10 = 270/280 - Subtract the two like fractions:
126/280 - 270/280 = 126 - 270/280 = -144/280 - After reducing the fraction, the answer is -18/35
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