Answer
$4ab+2a-5b$
Work Step by Step
Using the property: $\displaystyle \quad\frac{A+B}{C}=\frac{A}{C}+\frac{B}{C},$
$\displaystyle \frac{12a^{2}b^{2}+6a^{2}b-15ab^{2}}{3ab}=\frac{12a^{2}b^{2}}{3ab}+\frac{6a^{2}b}{3ab}-\frac{15ab^{2}}{3ab}$
= $4ab+2a-5b$
