Subtract 84/18 from 4/42, Solve 4/42

Subtract 84/18 from 4/42

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

4/42 - 84/18 is -32/7.

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,
4/42 = 4 × 3/42 × 3 = 12/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
84/18 = 84 × 7/18 × 7 = 588/126
Subtract the two like fractions:
12/126 - 588/126 = 12 - 588/126 = -576/126
After reducing the fraction, the answer is -32/7

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