Here's one of the reasons I like to teach freshmen. A conversation today:
Student: How long has Chipotle been around? Did it exist in the 1940's?
Me: I hope you aren't asking me that because you think I have first-hand experience.
Student: No, no! You're 30.
Me: (pause) That's about right.
Student: Because you were born in the 60's. Correct?
Me: (another pause) Yes.
There are so many opportunities during the course of the day to make immediate corrections but sometimes it's nice to let things work themselves out on their own. This young man may put two and two together at some point and he'll get the "ah ha."
As to the math, I will not say our math department is to blame because they haven't had enough time with him yet. His interpretation skills (how close he came to my real age), however, are obviously sharp from the short time with me. :)