Subtract 1/18 from 21/27
21/27 - 1/18 is 13/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 18 is 54
Next, find the equivalent fraction of both fractional numbers with denominator 54 - For the 1st fraction, since 27 × 2 = 54,
21/27 = 21 × 2/27 × 2 = 42/54 - Likewise, for the 2nd fraction, since 18 × 3 = 54,
1/18 = 1 × 3/18 × 3 = 3/54 - Subtract the two like fractions:
42/54 - 3/54 = 42 - 3/54 = 39/54 - After reducing the fraction, the answer is 13/18
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