Discussion of Question with ID = 013 under Problems-on-Trains

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Question

A train of length 190 m crosses a bridge at a speed of 45 km/h in 21 seconds. What is the length of the bridge?

A

72.5 meters.

B

60 meters.

C

262.5 meters.

D

150 meters.

Soln.
Ans: a

In 21 seconds the train covers a distance of 21 × 45 × (5/18) = 262.5 meters. This distance is the sum of the lengths of the train and the bridge. Subtracting the length of the train we get the length of the bridge = 262.5 - 190 = 72.5 meters.


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