A goods train runs at the speed of 72 kmph and crosses a 250 m long platform in 36 seconds. What is the length of the goods train?
Pick:
A) 470 m  B) 240 m  C) 260 m  D) 270 m  E) none of these

Rationale: "explanation : speed = [ 72 x ( 5 / 18 ) ] m / sec = 20 m / sec . time = 36 sec . let the length of the train be x metres . then , [ ( x + 250 ) / 36 ] = 20 = > x + 250 = 720 = > x = 470 . answer : a"
Answer: A