A train running at a speed of 36 kmph crosses an electric pole in 12 seconds. In how much time will it cross a 380 m long platform?
Select:
A) 50
B) 27
C) 29
D) 47
E) 28

Rationale: "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 + 380 ) / 36 * 5 / 18 = 50 min . answer : a"
Answer: A