Algebra — practice question

The polynomial $3x^3 + pax^2 + 7a^2x + qa^3$ is represented by $f(x)$, with $p$, $q$ and $a$ as constants and $a \neq 0$. If $f(x)$ is divided by $(x + 2a)$, the remainder is $-22a^3$. If $f(x)$ is divided by $(3x - a)$, the remainder is $-a^3$.