Subtract 81/84 from 5/21
5/21 - 81/84 is -61/84.
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,
5/21 = 5 × 4/21 × 4 = 20/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
81/84 = 81 × 1/84 × 1 = 81/84 - Subtract the two like fractions:
20/84 - 81/84 = 20 - 81/84 = -61/84
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