Subtract 30/12 from 5/81, Solve 5/81

Subtract 30/12 from 5/81

1^st number: 5/81, 2^nd number: 2 6/12

5/81 - 30/12 is -395/162.

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,
5/81 = 5 × 4/81 × 4 = 20/324
Likewise, for the 2nd fraction, since 12 × 27 = 324,
30/12 = 30 × 27/12 × 27 = 810/324
Subtract the two like fractions:
20/324 - 810/324 = 20 - 810/324 = -790/324
After reducing the fraction, the answer is -395/162

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