Answer
$20$
Work Step by Step
Formula to calculate the sum of the infinite terms of a geometric sequence is: $s_n=\dfrac{a_1}{(1-r)}$
Here, $r=\dfrac{a_2}{a_1}=-0.3$
As we are given that, $n=\infty$
Thus, $s_{\infty}=\dfrac{26}{(1-(-0.3))}$
or, $s_{\infty}=20$