Subtract 90/84 from 5/42
1st number: 5/42, 2nd number: 1 6/84
5/42 - 90/84 is -20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
5/42 = 5 × 2/42 × 2 = 10/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
90/84 = 90 × 1/84 × 1 = 90/84 - Subtract the two like fractions:
10/84 - 90/84 = 10 - 90/84 = -80/84 - After reducing the fraction, the answer is -20/21
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