$\frac{ 13171 }{ 4 } \times 20 \%$
$\frac{ 13171 }{ 4 } \times \frac{ 20 }{ 100 }$
$13171 \times \frac{ 5 }{ 100 }$
$13171 \times \frac{ 1 }{ 20 }$
$\begin{align*}&\frac{ 13171 }{ 20 } \\&\begin{array} { l }658 \frac{ 11 }{ 20 },& 658.55\end{array}\end{align*}$