Subtract 20/84 from 30/81
30/81 - 20/84 is 25/189.
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,
30/81 = 30 × 28/81 × 28 = 840/2268 - Likewise, for the 2nd fraction, since 84 × 27 = 2268,
20/84 = 20 × 27/84 × 27 = 540/2268 - Subtract the two like fractions:
840/2268 - 540/2268 = 840 - 540/2268 = 300/2268 - After reducing the fraction, the answer is 25/189
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