what’s the likelihood of this being on exam? nCx p^x (1-p)^n-x mean = np vari = np(1-p) phew.
I think that can be done on the calc. I have never understood it though. Check your 2nd + and - signs.
I just remember that permuation (NPR) means “order matters” and in NCR, order does not matter. Every question I have seen with this, I have been able to use the NPR/NCR function on my TI BAII Plus Calculator.
it can be done in calc, only if you understand that binomial probability needs to be applied to a given problem.
Forget about the exam - you can’t lead a happy and productive life without knowing those formulas. Get a sharpie, write it on your hand and you will know it by the time the marker wears off.
intuitively binomial formula makes a lot of sense. the guy who invented it gotta be a smart mofo.
Cool sox, kind of like NPR is a pretty formal radio station so order would matter 
Joey, you are in big trouble if that sharpie doesn’t wear off by the time I walk in the exam!
That’s a point…