Subtract 18/20 from 15/27
15/27 - 18/20 is -31/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 20 is 540
Next, find the equivalent fraction of both fractional numbers with denominator 540 - For the 1st fraction, since 27 × 20 = 540,
15/27 = 15 × 20/27 × 20 = 300/540 - Likewise, for the 2nd fraction, since 20 × 27 = 540,
18/20 = 18 × 27/20 × 27 = 486/540 - Subtract the two like fractions:
300/540 - 486/540 = 300 - 486/540 = -186/540 - After reducing the fraction, the answer is -31/90
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