Subtract 40/54 from 84/42, Solve 2 0/42

Subtract 40/54 from 84/42

1^st number: 2 0/42, 2^nd number: 40/54

84/42 - 40/54 is 34/27.

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

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
84/42 = 84 × 9/42 × 9 = 756/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
40/54 = 40 × 7/54 × 7 = 280/378
Subtract the two like fractions:
756/378 - 280/378 = 756 - 280/378 = 476/378
After reducing the fraction, the answer is 34/27
In mixed form: 17/27

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