$\"\"$

The sum of an infinete geometric series is $\"\"$ , with $\"\"$ ,

Where $\"\"$ is first term and r is common ratio.

The infinite geometric series is 3 + 1.8 + 1.08 + .............

In the above series $\"\"$ .

$\"\"$ , the sum exists. $\"\"$

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Subtract denominator: $\"\"$ )

= 7.5 (Divide: $\"\"$ ) $\"\"$

The sum of the infinite geometric series is 7.5.