Subtract 1/81 from 2/20, Solve 2/20

Subtract 1/81 from 2/20

2/20 - 1/81 is 71/810.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620

Next, find the equivalent fraction of both fractional numbers with denominator 1620
For the 1st fraction, since 20 × 81 = 1620,
2/20 = 2 × 81/20 × 81 = 162/1620
Likewise, for the 2nd fraction, since 81 × 20 = 1620,
1/81 = 1 × 20/81 × 20 = 20/1620
Subtract the two like fractions:
162/1620 - 20/1620 = 162 - 20/1620 = 142/1620
After reducing the fraction, the answer is 71/810

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