In a University the average age in an arts class is 21 and average age in technical class is 18. What is the age average of University if there are 8 arts classes and 5 technical classes? Answers:
A) 18.75
B) 19.85
C) 20.32
D) 20.9
E) 21.0

Rationale: average age of university = ( ( 8 x 21 ) + ( 5 x 18 ) ) / 13 = 19.85 answer : b
Answer: B