Subtract 21/14 from 30/54, Solve 30/54

Subtract 21/14 from 30/54

1^st number: 30/54, 2^nd number: 1 7/14

30/54 - 21/14 is -17/18.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 14 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
30/54 = 30 × 7/54 × 7 = 210/378
Likewise, for the 2nd fraction, since 14 × 27 = 378,
21/14 = 21 × 27/14 × 27 = 567/378
Subtract the two like fractions:
210/378 - 567/378 = 210 - 567/378 = -357/378
After reducing the fraction, the answer is -17/18

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