How do you simplify (12a^-9b^-4)/(9a^2b^6) using only positive exponents?

$\frac{4}{3 {a}^{11} {b}^{10}}$
Recall: Law of indices ${x}^{-} m = \frac{1}{x} ^ m$
$\frac{12 {a}^{-} 9 {b}^{-} 4}{9 {a}^{2} {b}^{6}}$ = $\frac{12}{9 {a}^{2} {a}^{9} {b}^{6} {b}^{4}}$
=$\frac{4}{3 {a}^{11} {b}^{10}}$