Subtract 90/42 from 18/84
1st number: 18/84, 2nd number: 2 6/42
18/84 - 90/42 is -27/14.
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,
18/84 = 18 × 1/84 × 1 = 18/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
90/42 = 90 × 2/42 × 2 = 180/84 - Subtract the two like fractions:
18/84 - 180/84 = 18 - 180/84 = -162/84 - After reducing the fraction, the answer is -27/14
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