I have no experience in caring for cichlids let alone a Ram. I know they can get about 2-3inches but will they be ok in a 10 gallon ttank with some ghost shrimp and 3 platys?
From personal experience with my Rams I would say the ghost shrimp will be lunch and the Platys will be fine. They might even eat the Platy fry though. They are really neat little fish.
Carol