Subtract 90/42 from 4/54, Solve 4/54

Subtract 90/42 from 4/54

1^st number: 4/54, 2^nd number: 2 6/42

4/54 - 90/42 is -391/189.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 42 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
4/54 = 4 × 7/54 × 7 = 28/378
Likewise, for the 2nd fraction, since 42 × 9 = 378,
90/42 = 90 × 9/42 × 9 = 810/378
Subtract the two like fractions:
28/378 - 810/378 = 28 - 810/378 = -782/378
After reducing the fraction, the answer is -391/189

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