It is really impossible to tell from that little information, or size in general. We do not know the eating habits, what they were fed etc..

I know my one male is about 2 years old and weighs prolly 17-18g, so if I did not know how old he was, I would assume he was much younger. He has been a spotty eater in the past (eats fine now) so even for a male he is on the small side. Just giving you an example.