Harleen,
Given that (1) you're burning exam time during a brain dump and (2) you probably won't be given decent writing materials to do one, I really suggest forgoing it and not relying on it for the exam. With respect to the formulas, you WILL need to know the basic earned value formulas and know how to manipulate them. It will be more important, however, to UNDERSTAND the definitions of each term in the performance indicator formulates, not just memorize them.
Also, with respect to the formulas, my advice is to do about 100 earned value/project estimating math problems and you should be set. I think the PrepCast had such a handout, but I cannot remember.
Best,
Harry