Answer
$9840$
Work Step by Step
The general formula to find the nth partial sum of a Geometric sequence is given as: $ S_{n}=\dfrac{a(1-r^n)}{(1-r)}$
$ a_1=3$ wen $ i=1$
Now, $ S_{8}=\dfrac{(3) \times (1-(3)^{8})}{(1-3)}=3 \times (-6560/2)$
Our answer is: $ S_{8}=9840$
