What is a good time for a girl to run 1 mile in track?

Well, I'm 12, and a girl, and I have started running recently with my older brother. (He used to run track.) I'm working at a 7:20-7:40 pace, working for 7:10 or even 7 minutes ;) I've only gotten up to 1.5 miles once but he tells me that as long as I run under 12 minutes I should be fine. It all depends on what type of runner you are. I guess 10 to 12 minutes is a good boundary. Hope this helps! :)