The speed of a car is 20 km in the first hour and 30 km in the second hour. What is the average speed of the car? Choose the correct option
A) 25 kmph  B) 85 kmph  C) 34 kmph  D) 23 kmph  E) 45 kmph

Rationale: "s = ( 20 + 30 ) / 2 = 25 kmph answer : a"
Answer: A