The given infinite geometric series is
[tex] \frac{1}{3},\, \frac{1}{9}, \, \frac{1}{27} , \, \frac{1}{81} , \, ...,[/tex]
The first term is a = 1/3.
The common ratio is r = 1/3.
The sum is
[tex] \frac{a}{1-r}= \frac{1/3}{1 - 1/3} = \frac{1}{2} [/tex]
Answer: 1/2