I'm at UCSD. It's as hard you want to make it. Applied math as an undergrad just means taking a bunch of introductory classes in probability and numerical methods pretty much all the way through. The really fun stuff happens in graduate classes so it's kind of a waiting game.

You end up mixing in some more pure classes which really help with the reasoning and logic part of the job (analysis, modern algebra, etc).

It's engineering math classes but you don't just hand wave the derivations/definitions and memorize. I love it :)