Subtract 12/21 from 18/84
18/84 - 12/21 is -5/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
18/84 = 18 × 1/84 × 1 = 18/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
12/21 = 12 × 4/21 × 4 = 48/84 - Subtract the two like fractions:
18/84 - 48/84 = 18 - 48/84 = -30/84 - After reducing the fraction, the answer is -5/14
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