Answer
$4$
Work Step by Step
RECALL:
$\log_b{a}-\log_b{c} = \log_b{(\frac{a}{c})}$
Use the rule above to obtain:
$=\log_3{(\frac{405}{5})}
\\=\log_3{81}$
Write $81$ as $3^4$ to obtain:
$=\log_3{3^4}$
Use the rule $\log_b{b^x} = x$ to obtain:
$=4$