Subtract 81/21 from 20/84
1st number: 20/84, 2nd number: 3 18/21
20/84 - 81/21 is -76/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
20/84 = 20 × 1/84 × 1 = 20/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Subtract the two like fractions:
20/84 - 324/84 = 20 - 324/84 = -304/84 - After reducing the fraction, the answer is -76/21
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