Answer
The series converges
$S_{\infty}= 16$
Work Step by Step
The common ratio of a geometric sequence is equal to the quotient of any term and the term before it:
$ \ r = \dfrac{a_n}{a_{n-1}}$ or, $r=\dfrac{a_2}{a_1}$
The sum of a convergent infinite geometric series is given by the formula:
$S_{\infty}=\dfrac{a_1}{1-r}$ and a geometric series converges if $|r| \lt 1$.
where $r$=common ratio and $a_1$= the first term
Now, $r=\dfrac{a_2}{a_1} = \dfrac{4}{8}=\dfrac{1}{2}$
Since $|\dfrac{1}{2}|\lt 1$, so the infinite geometric series converges.
Next, we will find the sum of the infinite geometric series when $a_1 = 8$ and $r=\dfrac{1}{2}$,
$S_{\infty} = \dfrac{a_1}{1-r} = \dfrac{8}{1-\dfrac{1}{2}}=\dfrac{8}{1/2}$
Therefore, the sum of the convergent infinite geometric series is: $S_{\infty}= 16$
