Subtract 70/18 from 8/42, Solve 8/42

Subtract 70/18 from 8/42

1^st number: 8/42, 2^nd number: 3 16/18

8/42 - 70/18 is -233/63.

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,
8/42 = 8 × 3/42 × 3 = 24/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
70/18 = 70 × 7/18 × 7 = 490/126
Subtract the two like fractions:
24/126 - 490/126 = 24 - 490/126 = -466/126
After reducing the fraction, the answer is -233/63

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