Subtract 90/84 from 20/21
1st number: 20/21, 2nd number: 1 6/84
20/21 - 90/84 is -5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
90/84 = 90 × 1/84 × 1 = 90/84 - Subtract the two like fractions:
80/84 - 90/84 = 80 - 90/84 = -10/84 - After reducing the fraction, the answer is -5/42
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