Subtract 36/42 from 18/56, Solve 18/56

Subtract 36/42 from 18/56

18/56 - 36/42 is -15/28.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 42 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
18/56 = 18 × 3/56 × 3 = 54/168
Likewise, for the 2nd fraction, since 42 × 4 = 168,
36/42 = 36 × 4/42 × 4 = 144/168
Subtract the two like fractions:
54/168 - 144/168 = 54 - 144/168 = -90/168
After reducing the fraction, the answer is -15/28

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