Subtract 42/12 from 30/54, Solve 30/54

Subtract 42/12 from 30/54

1^st number: 30/54, 2^nd number: 3 6/12

30/54 - 42/12 is -53/18.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 12 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 54 × 2 = 108,
30/54 = 30 × 2/54 × 2 = 60/108
Likewise, for the 2nd fraction, since 12 × 9 = 108,
42/12 = 42 × 9/12 × 9 = 378/108
Subtract the two like fractions:
60/108 - 378/108 = 60 - 378/108 = -318/108
After reducing the fraction, the answer is -53/18

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