Thinking about the newer bats (Duke, Cass, Steph, Tim) speculating on Jason's age because he looks like a recently divorced 30 y/o but he's younger than Dick, and he acts like a 50 year old man (he still has a Nokia, out of the loop on Internet and pop culture, primarily listens to dad rock), and after they've exhausted all their guesses Dick breezes in, informs them he's like 24, and then leaves.
The bats then have to come to terms with the fact that Jason NINETEEN when he took over the criminal underground.