Subtract 21/18 from 18/27
1st number: 18/27, 2nd number: 1 3/18
18/27 - 21/18 is -1/2.
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,
18/27 = 18 × 2/27 × 2 = 36/54 - Likewise, for the 2nd fraction, since 18 × 3 = 54,
21/18 = 21 × 3/18 × 3 = 63/54 - Subtract the two like fractions:
36/54 - 63/54 = 36 - 63/54 = -27/54 - After reducing the fraction, the answer is -1/2
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