Subtract 21/54 from 18/28
18/28 - 21/54 is 16/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 54 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 54 × 14 = 756,
21/54 = 21 × 14/54 × 14 = 294/756 - Subtract the two like fractions:
486/756 - 294/756 = 486 - 294/756 = 192/756 - After reducing the fraction, the answer is 16/63
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