A train 400 m long can cross an electric pole in 40 sec and then find the speed of the train?  Choose the correct choice from the following
A) 36 kmph  B) 40 kmph  C) 42 kmph  D) 45 kmph  E) 38 kmph

Rationale: "length = speed * time speed = l / t s = 400 / 40 s = 10 m / sec speed = 10 * 18 / 5 ( to convert m / sec in to kmph multiply by 18 / 5 ) speed = 36 kmph answer : a"
Answer: A