Straighterline grading?

[humbleAMG]

I am down to the final in Western civilization 1 and have a 96% overall. I am trying to find out how to calculate the grade I need to get on the final to pass with a 70%.
Sorry if this has been asked before just have trouble figuring out their points system.

I'm about to take my final in WesternCiv and going into with the same 96%. So with my current 720 I passed but would like to get this up past 90%. Fingers crossed. 2 hrs and counting. EDIT: Scored 80% 200/250. Not bad for no texbook, just by memory. So overall score of 92% for the class.