Subtract 7/84 from 5/81
5/81 - 7/84 is -7/324.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 84 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 81 × 28 = 2268,
5/81 = 5 × 28/81 × 28 = 140/2268 - Likewise, for the 2nd fraction, since 84 × 27 = 2268,
7/84 = 7 × 27/84 × 27 = 189/2268 - Subtract the two like fractions:
140/2268 - 189/2268 = 140 - 189/2268 = -49/2268 - After reducing the fraction, the answer is -7/324
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