A train is 360 meter long is running at a speed of 50 km/hour. In what time will it pass a bridge of 140 meter length?
Choose the correct choice.
A) 87
B) 69
C) 36
D) 72
E) 21

Rationale: "speed = 50 km / hr = 50 * ( 5 / 18 ) m / sec = 125 / 9 m / sec total distance = 360 + 140 = 500 meter time = distance / speed = 500 * ( 9 / 125 ) = 36 seconds answer : c"
Answer: C