Subtract 21/7 from 81/84
1st number: 81/84, 2nd number: 3 0/7
81/84 - 21/7 is -57/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
81/84 = 81 × 1/84 × 1 = 81/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
21/7 = 21 × 12/7 × 12 = 252/84 - Subtract the two like fractions:
81/84 - 252/84 = 81 - 252/84 = -171/84 - After reducing the fraction, the answer is -57/28
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