Answer
$\log_5 125=3$
Work Step by Step
Using the properties of logarithms, the given expression, $\log_5 125,$ is equivalent to
\begin{align*}\require{cancel}
&
\log_5 5^3
\\&=
3\log_5 5
&(\log_b m^n=n\log_b m)
\\&=
3(1)
&(\log_b b=1)
\\&=
3
.\end{align*}Hence, the expression $\log_5 125$ simplifies to $3$.
