Evaluate the following geometric sum.

${\displaystyle \underset{k=0}{\overset{5}{}}}(-\frac{3}{4}{)}^k$

${\displaystyle \underset{k=0}{\overset{5}{}}}(-\frac{3}{4}{)}^k=0\mathrm{.}4697$

$(Do$ not round until the final answer. Then round $to$ four decimal places $as$ needed.$)$