Subtract 20/27 from 18/28
18/28 - 20/27 is -37/378.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 27 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 28 × 27 = 756,
18/28 = 18 × 27/28 × 27 = 486/756 - Likewise, for the 2nd fraction, since 27 × 28 = 756,
20/27 = 20 × 28/27 × 28 = 560/756 - Subtract the two like fractions:
486/756 - 560/756 = 486 - 560/756 = -74/756 - After reducing the fraction, the answer is -37/378
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