"Being able to calculate" is fine (though I'd like a more clear test that doesn't require the user to generate random numbers), but "being able to explain" is not nearly crisp enough. It's almost as bad as using "being able to explain why politics is the mind-killer" as part of a test for rationality. Could you rethink that part?
OK, here's my revised version for finance:
You should be able to figure out how much money you will pay in compound interest on a loan, or how much you will earn on an interest bearing account, in a fixed amount of time.
You should be able to compare the monetary values of different financial decisions (e.g. borrowing money, paying off a loan, purchasing an investment) by comparing their present value.
I just got this random idea that people who want to become better at life could benefit from a common scale of "leveling". No, I don't mean vague Lesswrongey things like "changing your mind". I mean a set of concrete criteria like "you qualify for level 2 if you can do 5 pull-ups, have solved 30 Project Euler problems, and did 10 cold approaches". Obviously there would be separate ladders for different character classes, but not too many. Also obviously, my example was a bit too high for level 2. So I guess I really want to ask some meta questions here:
1) Do you think agreeing on a common leveling scale would be a good thing for a substantial subset of LW users? Would you feel good about leveling up and telling other people about it on LW?
2) Is there some good way to determine leveling criteria that are neither too high nor too low? Maybe make an intermediate scale of "experience points"?