Subtract 18/14 from 21/27, Solve 21/27

Subtract 18/14 from 21/27

1^st number: 21/27, 2^nd number: 1 4/14

21/27 - 18/14 is -32/63.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 14 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 27 × 14 = 378,
21/27 = 21 × 14/27 × 14 = 294/378
Likewise, for the 2nd fraction, since 14 × 27 = 378,
18/14 = 18 × 27/14 × 27 = 486/378
Subtract the two like fractions:
294/378 - 486/378 = 294 - 486/378 = -192/378
After reducing the fraction, the answer is -32/63

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