The average of 5 quantities is 9. The average of 3 of them is 4. What is the average of remaining 2 numbers?	Select:  A) 16.5  B) 10  C) 8  D) 9.5  E) none of these

Rationale: "answer : a ( 5 x 9 - 3 x 4 ) / 2 = 16.5"
Answer: A