Subtract 5/18 from 21/84
21/84 - 5/18 is -1/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
5/18 = 5 × 14/18 × 14 = 70/252 - Subtract the two like fractions:
63/252 - 70/252 = 63 - 70/252 = -7/252 - After reducing the fraction, the answer is -1/36
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