Answer
$5460$
Work Step by Step
Formula to calculate the sum of the first $n$ terms of a geometric sequence is: $s_n=\dfrac{a(1-r^n)}{(1-r)}$
Here, $r=\dfrac{a_2}{a_1}=4$
As we are given that, $n=6$
Thus, $s_{6}=\dfrac{4(1-4^{6})}{(1-4)}$
or, $s_{6}=5460$