Subtract 12/9 from 3/42, Solve 3/42

Subtract 12/9 from 3/42

1^st number: 3/42, 2^nd number: 1 3/9

3/42 - 12/9 is -53/42.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
3/42 = 3 × 3/42 × 3 = 9/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126
Subtract the two like fractions:
9/126 - 168/126 = 9 - 168/126 = -159/126
After reducing the fraction, the answer is -53/42

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