Subtract 42/12 from 90/54, Solve 1 36/54

Subtract 42/12 from 90/54

1^st number: 1 36/54, 2^nd number: 3 6/12

90/54 - 42/12 is -11/6.

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,
90/54 = 90 × 2/54 × 2 = 180/108
Likewise, for the 2nd fraction, since 12 × 9 = 108,
42/12 = 42 × 9/12 × 9 = 378/108
Subtract the two like fractions:
180/108 - 378/108 = 180 - 378/108 = -198/108
After reducing the fraction, the answer is -11/6

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