# ?How do you find the sum of the infinite geometric series 4+2+1+1/2+1/4 ...

Nov 11, 2015

The sum of an infinite geometric series is:
$S = \frac{{a}_{1}}{1 - r}$

#### Explanation:

For this problem, $r = \frac{1}{2}$ and ${a}_{1} = 4$

$S = \frac{{a}_{1}}{1 - r} = \frac{4}{1 - \frac{1}{2}} = 8$

hope that helped