Answer
2.5164
Work Step by Step
We know that logarithms to base 10 are common logarithms, and $log_{10}x$ is equivalent to $log(x)$.
Therefore, $log(328.4)=log_{10}328.4$.
We know that for all positive numbers $a$ (where $a\ne1$), and all positive numbers $x$, $y=log_{a}x$ means the same as $x=a^{y}$.
Therefore, $log_{10}328.4\approx2.5164$, because $10^{2.5164}\approx328.4$.