Subtract 21/27 from 3/12
3/12 - 21/27 is -19/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 27 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 12 × 9 = 108,
3/12 = 3 × 9/12 × 9 = 27/108 - Likewise, for the 2nd fraction, since 27 × 4 = 108,
21/27 = 21 × 4/27 × 4 = 84/108 - Subtract the two like fractions:
27/108 - 84/108 = 27 - 84/108 = -57/108 - After reducing the fraction, the answer is -19/36
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