Subtract 30/18 from 50/42, Solve 1 8/42

Subtract 30/18 from 50/42

1^st number: 1 8/42, 2^nd number: 1 12/18

50/42 - 30/18 is -10/21.

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,
50/42 = 50 × 3/42 × 3 = 150/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126
Subtract the two like fractions:
150/126 - 210/126 = 150 - 210/126 = -60/126
After reducing the fraction, the answer is -10/21

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