Prove that a group of order $p^2q$ has a proper normal subgroup and is solvable. So, going through my qual prep classes, there's a two part question:  For $p,q$ distinct primes, prove that a group of order $p^2q$ has a nontrivial proper normal subgroup,  then prove that it's solvable.  Part 2 is pretty trivial given the first, but I've been struggling with it.
Thoughts so far:  Attacking with Sylow theorems, if $n_p=1$ or $n_q=1$ we'd be done,  so assume neither are one (either for contradiction or to find a group of order $pq$, since I'll show later that such a group would have to be normal)
So,  given that we need $n_p=q$ and $n_q=p$ or $n_q=p^2$,  but since we also need $n_p>p$ and $n_q>q$,  we must have $p<q<p^2$, and $n_q=p^2$.  We also have $q=pk+1$ and $p^2=qj+1$ for some natural numbers $k,j$ due to congruency,  but I couldn't seem to find a contradiction out of here.
Now, since $p$ is the smallest prime,  if I could find a subgroup of order $pq$, it would have index $p$ and thus be normal by the theorem that groups of the smallest prime index of a group are normal.  However, I can't seem to figure out why either that would have to be the case, or why the above statements are a contradiction to force a normal $p^2$ group or a normal $q$ group.  
 A: For the contradiction: Since $p^2-1=qj$ then $p^2-1$ is a multiple of $q$. Hence, $q$ divides $p-1$ or $p+1$. Since $q>p$ then $q=p+1$, which implies $q=3$ and $p=2$.
This paper lists all possible groups of order $12$ (and includes a proof that none of them are simple).
A: You can use a counting argument.  Note that if there are $p^2$ subgroups of order $q$, each of them has $q-1$ distinct elements of order $q$ generating that subgroup.  Thus, only $p^2 = p^2q - p^2(q-1)$ elements can have orders $1, p, p^2$.  This implies that there can be only one subgroup of order $p^2$, as desired.
A: Hint: If there are $q$ Sylow $p$-subgroups, then either two of them intersect non-trivially, or between them the Sylow $p$-subgroups cover $1+q(p^2-1)=p^2q-(q-1)$ elements.


*

*In the latter case there is room for only a single Sylow $q$-subgroups.

*In the former case let $H$ be a non-trivial intersection of two Sylow $p$-subgroups: $H=P_1\cap P_2$. Show that the normalizer of $H$ has more than $p^2$ elements.

