Subtract 6/8 from 15/42, Solve 15/42

Subtract 6/8 from 15/42

15/42 - 6/8 is -11/28.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 42 × 4 = 168,
15/42 = 15 × 4/42 × 4 = 60/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
6/8 = 6 × 21/8 × 21 = 126/168
Subtract the two like fractions:
60/168 - 126/168 = 60 - 126/168 = -66/168
After reducing the fraction, the answer is -11/28

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