$=\frac{3\cdot 13p^{4}q^{5}}{3p^{2}q^{2}}$
$=\frac{13p^{4}q^{5}}{p^{2}q^{2}}$
$=\frac{13p^{2}q^{5}}{q^{2}}$
$=13p^{2}q^{3}$