Subtract 42/45 from 12/27, Solve 12/27

Subtract 42/45 from 12/27

12/27 - 42/45 is -22/45.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 45 is 135

Next, find the equivalent fraction of both fractional numbers with denominator 135
For the 1st fraction, since 27 × 5 = 135,
12/27 = 12 × 5/27 × 5 = 60/135
Likewise, for the 2nd fraction, since 45 × 3 = 135,
42/45 = 42 × 3/45 × 3 = 126/135
Subtract the two like fractions:
60/135 - 126/135 = 60 - 126/135 = -66/135
After reducing the fraction, the answer is -22/45

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