Subtract 42/81 from 1/12, Solve 1/12

Subtract 42/81 from 1/12

1/12 - 42/81 is -47/108.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 12 × 27 = 324,
1/12 = 1 × 27/12 × 27 = 27/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
42/81 = 42 × 4/81 × 4 = 168/324
Subtract the two like fractions:
27/324 - 168/324 = 27 - 168/324 = -141/324
After reducing the fraction, the answer is -47/108

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