Subtract 5/18 from 42/12, Solve 3 6/12

Subtract 5/18 from 42/12

1^st number: 3 6/12, 2^nd number: 5/18

42/12 - 5/18 is 29/9.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 12 × 3 = 36,
42/12 = 42 × 3/12 × 3 = 126/36
Likewise, for the 2nd fraction, since 18 × 2 = 36,
5/18 = 5 × 2/18 × 2 = 10/36
Subtract the two like fractions:
126/36 - 10/36 = 126 - 10/36 = 116/36
After reducing the fraction, the answer is 29/9
In mixed form: 32/9

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