Subtract 84/18 from 5/42, Solve 5/42

Subtract 84/18 from 5/42

1^st number: 5/42, 2^nd number: 4 12/18

5/42 - 84/18 is -191/42.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
5/42 = 5 × 3/42 × 3 = 15/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
84/18 = 84 × 7/18 × 7 = 588/126
Subtract the two like fractions:
15/126 - 588/126 = 15 - 588/126 = -573/126
After reducing the fraction, the answer is -191/42

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