A train 100 m long can cross an electric pole in 20 sec and then find the speed of the train?
Answers:
A) 19 kmph
B) 18 kmph
C) 72 kmph
D) 17 kmph
E) 91 kmph

Rationale: "length = speed * time speed = l / t s = 100 / 20 s = 5 m / sec speed = 5 * 18 / 5 ( to convert m / sec in to kmph multiply by 18 / 5 ) speed = 18 kmph answer : b"
Answer: B