The length of the bridge, which a train 120 metres long and travelling at 45 km/hr can cross in 30 seconds, is: Choose the correct choice from the following options
A) 230 B) 240 C) 245 D) 255 E) 260

Rationale: "speed = [ 45 x 5 / 18 ] m / sec = [ 25 / 2 ] m / sec time = 30 sec let the length of bridge be x metres . then , ( 120 + x ) / 30 = 25 / 2 = > 2 ( 120 + x ) = 750 = > x = 255 m . answer : option d"
Answer: D