The length of the bridge, which a train 170 metres long and travelling at 45 km/hr can cross in 30 seconds, is: Choose the correct choice from the following choices.
A) 205
B) 210
C) 215
D) 250
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 , ( 170 + x ) / 30 = 25 / 2 = > 2 ( 170 + x ) = 750 = > x = 205 m . answer : option a"
Answer: A