Subtract 20/81 from 3/84
3/84 - 20/81 is -479/2268.
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,
3/84 = 3 × 27/84 × 27 = 81/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
20/81 = 20 × 28/81 × 28 = 560/2268 - Subtract the two like fractions:
81/2268 - 560/2268 = 81 - 560/2268 = -479/2268
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