Answer
$7a^{3}b^{10}$
Work Step by Step
Based on the power of a quotient rule, we know that $\frac{a^{m}}{{a}^{n}}=a^{m-n}, a\ne0$ (where $m$ and $n$ are positive integers and $a$ is a real number).
Therefore, $\frac{7a^{4}b^{11}}{ab}=7\times a^{4-1}\times b^{11-1}=7a^{3}b^{10}$.