Subtract 15/28 from 21/27
21/27 - 15/28 is 61/252.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 28 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 27 × 28 = 756,
21/27 = 21 × 28/27 × 28 = 588/756 - Likewise, for the 2nd fraction, since 28 × 27 = 756,
15/28 = 15 × 27/28 × 27 = 405/756 - Subtract the two like fractions:
588/756 - 405/756 = 588 - 405/756 = 183/756 - After reducing the fraction, the answer is 61/252
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