Subtract 9/18 from 21/54
21/54 - 9/18 is -1/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 18 is 54
Next, find the equivalent fraction of both fractional numbers with denominator 54 - For the 1st fraction, since 54 × 1 = 54,
21/54 = 21 × 1/54 × 1 = 21/54 - Likewise, for the 2nd fraction, since 18 × 3 = 54,
9/18 = 9 × 3/18 × 3 = 27/54 - Subtract the two like fractions:
21/54 - 27/54 = 21 - 27/54 = -6/54 - After reducing the fraction, the answer is -1/9
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