A train 360 m long runs with a speed of 45 km/hr. What time will it take to pass a platform of 180 m long?
Choose the correct choice from the following answers.
A) 38 sec  B) 35 sec  C) 43.2 sec  D) 40 sec  E) none of these

Rationale: "speed = 45 km / hr = 45 ã — ( 5 / 18 ) m / s = 150 / 12 = 50 / 4 = 25 / 2 m / s total distance = length of the train + length of the platform = 360 + 180 = 540 meter time taken to cross the platform = 540 / ( 25 / 2 ) = 540 ã — 2 / 25 = 43.2 seconds answer : c"
Answer: C