Subtract 21/27 from 20/28
20/28 - 21/27 is -4/63.
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,
20/28 = 20 × 27/28 × 27 = 540/756 - Likewise, for the 2nd fraction, since 27 × 28 = 756,
21/27 = 21 × 28/27 × 28 = 588/756 - Subtract the two like fractions:
540/756 - 588/756 = 540 - 588/756 = -48/756 - After reducing the fraction, the answer is -4/63
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