Subtract 21/42 from 8/27, Solve 8/27

Subtract 21/42 from 8/27

8/27 - 21/42 is -11/54.

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,
8/27 = 8 × 14/27 × 14 = 112/378
Likewise, for the 2nd fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378
Subtract the two like fractions:
112/378 - 189/378 = 112 - 189/378 = -77/378
After reducing the fraction, the answer is -11/54

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