Subtract 30/12 from 3/81, Solve 3/81

Subtract 30/12 from 3/81

1^st number: 3/81, 2^nd number: 2 6/12

3/81 - 30/12 is -133/54.

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

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 81 × 4 = 324,
3/81 = 3 × 4/81 × 4 = 12/324
Likewise, for the 2nd fraction, since 12 × 27 = 324,
30/12 = 30 × 27/12 × 27 = 810/324
Subtract the two like fractions:
12/324 - 810/324 = 12 - 810/324 = -798/324
After reducing the fraction, the answer is -133/54

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