Subtract 42/27 from 12/15, Solve 12/15

Subtract 42/27 from 12/15

1^st number: 12/15, 2^nd number: 1 15/27

12/15 - 42/27 is -34/45.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 27 is 135

Next, find the equivalent fraction of both fractional numbers with denominator 135
For the 1st fraction, since 15 × 9 = 135,
12/15 = 12 × 9/15 × 9 = 108/135
Likewise, for the 2nd fraction, since 27 × 5 = 135,
42/27 = 42 × 5/27 × 5 = 210/135
Subtract the two like fractions:
108/135 - 210/135 = 108 - 210/135 = -102/135
After reducing the fraction, the answer is -34/45

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