Subtract 42/81 from 8/84
8/84 - 42/81 is -80/189.
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,
8/84 = 8 × 27/84 × 27 = 216/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
42/81 = 42 × 28/81 × 28 = 1176/2268 - Subtract the two like fractions:
216/2268 - 1176/2268 = 216 - 1176/2268 = -960/2268 - After reducing the fraction, the answer is -80/189
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