The length of the bridge, which a train 135 m long and traveling at 45 km/hr can cross in 30 sec is? Choose the correct choice from the following:
A) 235
B) 240
C) 245
D) 250
E) 255

Rationale: "speed = 45 * 5 / 18 = 25 / 2 m / sec . time = 30 sec let the length of bridge be x meters . then , ( 135 + x ) / 30 = 25 / 2 x = 240 m . answer : option b"
Answer: B