TITLE: Group of order 30 can't be simple
QUESTION [6 upvotes]: I have this following question from my class note on Sylow Theorem:

Show that a group of order 30 can not be simple.

For that I know the followings:
(1) A simple group is one that does not have non-trivial normal group, 
(2) Group $G$ is p-group if there exists an integer $e$ such that $|G| = p^e,$ 
(3) A $p$-subgroup $H$ of $G$ is called Sylow p-subgroup of $G$ if $p \nmid |G/H|,$ and finally 
(4) A subgroup $H$ of $G$ is a Sylow p-subgroup if there exist integers $e$ and $m$ such that $|G| = p^em,$ and $(e, m) = 1,$ and also $|H| = p^e,$
but unfortunately I don't know how to weave them into a solution, any help would therefore be very much appreciated. Thank you for your time and help.
PS. If you have choices of elegant versus dummy down-to-earth solutions, do please give me the latter. I know it would be tedious for you but you have a slowpoke turtle down here. Thank again for your patience.
POST SCRIPT : ~~~~~~~~~~~~~~~~~~~~~~~ 
I came across a very simple solution by John Beachy here, consisting of only 2 lines, which I adapted to fit group order of 30:
EDIT (j.p.) Unfortunately the linked solution cannot be easily adapted to this case here. I kept the text as far it was correct.
(1) Recall Sylow's Theorem: If $|G| = p^em; p, e, m \in \mathbb Z^+; (p, m) = 1;$ the number of $Syl_p (G) = s$, then $s \equiv 1\pmod p$ and $s \mid m.$ 
(2) For $|G| = 5 \cdot 2 \cdot 3$, suppose that $p = 5, e = 1$ and $m = 6.$ Therefore $s \equiv 1\pmod 5 $ and $s \mid 6,$ thus $s = \{1, 6 \}$. The 5-Sylow subgroup is normal if and only if $s=1$, and in this case $G$ is not simple.
(3) Now look at Nirdonkey's answer.
Hope this will be useful for some of you and thank you very much for those of you who have helped me.

REPLY [5 votes]: By Cayley's theorem, a group $G$ of order $30$ is isomorphic to a subgroup of $S_{30}$ is such a way that no non-identity element of $G$ has any fixed point. There is an element $t$ of order $2$ in $G$ which is represented by a product of $15$ $2$-cycles, so as an odd permutation. The elements of $G$ which are represented as even permutations of $S_{30}$ form a normal subgroup of index $2$, so $G$ is not simple.