Subtract 70/42 from 7/18, Solve 7/18

Subtract 70/42 from 7/18

1^st number: 7/18, 2^nd number: 1 28/42

7/18 - 70/42 is -23/18.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
7/18 = 7 × 7/18 × 7 = 49/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
70/42 = 70 × 3/42 × 3 = 210/126
Subtract the two like fractions:
49/126 - 210/126 = 49 - 210/126 = -161/126
After reducing the fraction, the answer is -23/18

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