Well, the basic staff - know how to +, -, x, and divide.....know interest calculations, In higher stage know some statistics, some basic calculus ( a special brance of mathematics fromengineering, etc..) for calculating max or min profits, etc. if you sill go higher, you may have to learn "Game Theory" - for chance calculations, etc., and "quantitative programing" where you learn to find the best mix of available limited resources to make the maximun profit....however, all you need is basic arithmatic and good grey matter in your head.
