You should use the chi square test for independence.see attached.
If we have a table for two types of company which have either high or low risk sock given thus:
COMPANY TYPE LOW RISK HIGH RISK
Internet services .....6 ...............9
Financial Service .....20 ..............5
and we want to see if the company type is dependent or independent of the level of risk how do we do this?
I know if P(A intersect B) = P(A) times P(B) then we know the events are independent, and if those two expressions are not equal then we know they are dependent
how do I set up events A and B in this case?