I am currently looking whether a group G of the following order is simple or not
- $ord(G)=100$
- $ord(G')=200$
We have first that for $G$, $ord(G)=2^25^2$. For $G'$ we have that $ord(G')=2^35^2$. Now with the third theorem of Sylow we have, that in both case there is only one $5-$Sylowgroup. But why $G$ is not simple, while $G'$ is simple? I just try to follow the thinking of this site Click here