If 30% of a class averages 95% on a test, 50% of the class averages 79% on the test, and the remainder of the class averages 60% on the test, what is the overall class average? (Round final answer to the nearest percent). Choices:
A) 76 %  B) 77 %  C) 78 %  D) 79 %  E) 80 %

Rationale: "this question is a weighted average question with a series of dependent variables . the remaining portion of the class represents 100 % - 30 % - 50 % = 20 % of the class converting the portions of the class population to decimal weights , we find : class average = 0.30 x 95 + 0.50 x 79 + 0.20 x 60 = 80 the class average ( rounded ) is 80 % final answer e ) 80 %"
Answer: E