Answer
$\dfrac{4}{5}$
Work Step by Step
Formula to calculate the Nth partial sum of a geometric series is
$s_n=\dfrac{a(1-r^n)}{1-r}$
Formula to calculate the Sum of a geometric series can be found as:
$S=\dfrac{a}{1-r}$
Here, $r=\dfrac{-1}{4}, a=1$
Thus, $s_n=\dfrac{1(1-(\dfrac{-1}{4})^n)}{1-(\dfrac{-1}{4})}$
and $S=\dfrac{a}{1-r}=\dfrac{1}{\dfrac{5}{4}}=\dfrac{4}{5}$
