Subtract 20/42 from 10/27
10/27 - 20/42 is -20/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 27 × 14 = 378,
10/27 = 10 × 14/27 × 14 = 140/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
20/42 = 20 × 9/42 × 9 = 180/378 - Subtract the two like fractions:
140/378 - 180/378 = 140 - 180/378 = -40/378 - After reducing the fraction, the answer is -20/189
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