Subtract 81/12 from 21/84
1st number: 21/84, 2nd number: 6 9/12
21/84 - 81/12 is -13/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 12 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 12 × 7 = 84,
81/12 = 81 × 7/12 × 7 = 567/84 - Subtract the two like fractions:
21/84 - 567/84 = 21 - 567/84 = -546/84 - After reducing the fraction, the answer is -13/2
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