OK, this isn't for homework, it's a project I'm working on..I think this is the right forum.

I have 2 variables. A and B. B is an amount of points given out depending on much A is. A can be anywhere from 0.0 - 7.0. B can be carried out to several decimals as well, whatever the formula calls for. I have been given a few samples:

if A=2.5 then b=0

if A=4 then B=1

if A=5 then B=2

I need a formula here. I'll be given a value for A, so I need to solve for B...so that my formula is B=f(A)...not sure if this requires calc or what..