A train running at a speed of 36 kmph crosses an electric pole in 12 seconds. In how much time will it cross a 320 m long platform?  Choose the correct choice from the following
A) 44 min	B) 55 min	C) 47 min	D) 67 min	E) 45 min

Rationale: "a 44 min let the length of the train be x m . when a train crosses an electric pole , the distance covered is its own length . so , x = 12 * 36 * 5 / 18 m = 120 m . time taken to cross the platform = ( 120 + 320 ) / 36 * 5 / 18 = 44 min ."
Answer: A