Answer
$a_n=3(2)^{n-1}$, $S_{10} =3069$
Work Step by Step
Given the sequence $3,6,12,24,48$, we have $\frac{6}{3}=2, \frac{12}{6}=2...$ and it can be identified as a geometric sequence. We have $a_n=3(2)^{n-1}$ and $S_{10}=(3)\frac{1-2^{10}}{1-2}=3069$
