Subtract 7/81 from 4/30, Solve 4/30

Subtract 7/81 from 4/30

4/30 - 7/81 is 19/405.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810

Next, find the equivalent fraction of both fractional numbers with denominator 810
For the 1st fraction, since 30 × 27 = 810,
4/30 = 4 × 27/30 × 27 = 108/810
Likewise, for the 2nd fraction, since 81 × 10 = 810,
7/81 = 7 × 10/81 × 10 = 70/810
Subtract the two like fractions:
108/810 - 70/810 = 108 - 70/810 = 38/810
After reducing the fraction, the answer is 19/405

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