Subtract 1/27 from 20/42, Solve 20/42

Subtract 1/27 from 20/42

20/42 - 1/27 is 83/189.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
20/42 = 20 × 9/42 × 9 = 180/378
Likewise, for the 2nd fraction, since 27 × 14 = 378,
1/27 = 1 × 14/27 × 14 = 14/378
Subtract the two like fractions:
180/378 - 14/378 = 180 - 14/378 = 166/378
After reducing the fraction, the answer is 83/189

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