The length of the bridge, which a train 250 metres long and travelling at 72 km/hr can cross in 30 seconds, is:
Choose the correct choice from the following answers:
A) 200 m	B) 225 m	C) 245 m	D) 350 m	E) 240 m

Rationale: "speed = [ 72 x 5 / 18 ] m / sec = 20 m / sec time = 30 sec let the length of bridge be x metres . then , ( 250 + x ) / 30 = 20 = > 250 + x = 600 = > x = 350 m . answer : d"
Answer: D