Subtract 9/15 from 3/81, Solve 3/81

Subtract 9/15 from 3/81

3/81 - 9/15 is -76/135.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 15 is 405

Next, find the equivalent fraction of both fractional numbers with denominator 405
For the 1st fraction, since 81 × 5 = 405,
3/81 = 3 × 5/81 × 5 = 15/405
Likewise, for the 2nd fraction, since 15 × 27 = 405,
9/15 = 9 × 27/15 × 27 = 243/405
Subtract the two like fractions:
15/405 - 243/405 = 15 - 243/405 = -228/405
After reducing the fraction, the answer is -76/135

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