Subtract 14/42 from 21/84
21/84 - 14/42 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
14/42 = 14 × 2/42 × 2 = 28/84 - Subtract the two like fractions:
21/84 - 28/84 = 21 - 28/84 = -7/84 - After reducing the fraction, the answer is -1/12
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