Subtract 30/36 from 8/42, Solve 8/42

Subtract 30/36 from 8/42

8/42 - 30/36 is -9/14.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 42 × 6 = 252,
8/42 = 8 × 6/42 × 6 = 48/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
30/36 = 30 × 7/36 × 7 = 210/252
Subtract the two like fractions:
48/252 - 210/252 = 48 - 210/252 = -162/252
After reducing the fraction, the answer is -9/14

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