Subtract 12/24 from 1/81, Solve 1/81

Subtract 12/24 from 1/81

1/81 - 12/24 is -79/162.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 24 is 648

Next, find the equivalent fraction of both fractional numbers with denominator 648
For the 1st fraction, since 81 × 8 = 648,
1/81 = 1 × 8/81 × 8 = 8/648
Likewise, for the 2nd fraction, since 24 × 27 = 648,
12/24 = 12 × 27/24 × 27 = 324/648
Subtract the two like fractions:
8/648 - 324/648 = 8 - 324/648 = -316/648
After reducing the fraction, the answer is -79/162

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