Find the average of all the numbers between 6 and 34 which are divisible by 5?
Choose the most appropriate option.
A) 32 B) 20 C) 28 D) 11 E) 18

Rationale: "average = ( 10 + 15 + 20 + 25 + 30 ) / 5 = 100 / 5 = 20 . answer : b"
Answer: B