Answer
$\dfrac{5}{3}$
Work Step by Step
Here, $a=1, r=\dfrac{2}{5}$;
Since, $r=|\dfrac{2}{5}| \lt 1$;
Thus, the series converges.
Formula to find the sum of a geometric series is
$S=\dfrac{a}{1-r}$
Thus, $S=\dfrac{1}{1-\dfrac{2}{5}}=\dfrac{5}{3}$
