shell and age

by Starr
(Florida)

I just bought three tortoises. 2 babies and one that is about 6or7 inches long, 3-4 inches wide. I have no idea how old he is, and would really like to know so I can get an estimate on how big the babies will be in a few years depending. Also my main question is really, the bigger ones shell is very jagged on the bottom and is cutting into his back leg pretty badly. Can I file down his shell or something to stop this or will that hurt him?