Subtract 21/27 from 18/36
18/36 - 21/27 is -5/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 27 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 36 × 3 = 108,
18/36 = 18 × 3/36 × 3 = 54/108 - Likewise, for the 2nd fraction, since 27 × 4 = 108,
21/27 = 21 × 4/27 × 4 = 84/108 - Subtract the two like fractions:
54/108 - 84/108 = 54 - 84/108 = -30/108 - After reducing the fraction, the answer is -5/18
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