Can't read or write at all, but can do math problems?

I was the other way - no problem reading and writing, but numbers made no sense. I could not tell the time until I was in my late teens. Was considered a retard. Anyway, I grew out of it, now use maths a lot in my work (real maths like calculus etc). I'd have the teen get checked out by a professional. If he/she never learns to read and write their life is going to be crap....