Step 1:

The series is .

Rewrite the series .

The above series is look like a geometric series.

n^th term of the geometric series is .

First term of the geometric series .

Common ratio of the geometric series is .

Step 2:

Find the sum of the geometric series.

The above series is infinite geometric series with and .

When the sum of the geometric series is .

So the sum of the geometric series is 10.