Calculus Question please help

Question

Find the sum, if it exists, of the infinite geometric series,  .

	1
	Sum does not exist

Answer 1

common ratio = r = (3/5)/3 = (3/25)/(3/5) = ... = 1/5

Since r lies in the interval (-1,1), the series has a finite sum given by the formula a / (1-r), where a is the first term of the series.

So, the sum of the series is 3 / (1 - 1/5) = 3 / (4/5) = 15/4