Subtract 3/81 from 21/84
21/84 - 3/81 is 23/108.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 84 × 27 = 2268,
21/84 = 21 × 27/84 × 27 = 567/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
3/81 = 3 × 28/81 × 28 = 84/2268 - Subtract the two like fractions:
567/2268 - 84/2268 = 567 - 84/2268 = 483/2268 - After reducing the fraction, the answer is 23/108
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