Puzzle 67 - Solution

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 The question was

 A train is travelling at the speed of 96 kilometres per hour. It takes 3 seconds to enter a tunnel and 30 seconds more to pass through it completely. What is the length of the train and the tunnel?

 Solution:

      Time taken for the entire train(from front to rear) to enter the tunnel (from front to rear) = 3 seconds
      Distance traveled in 3 seconds = 3 X 96X1000/(60X60) meters = 80 meters
      80 meters is the length of the train 
 
       Time taken for train to pass through the tunnel = 30 seconds.
        Distance travelled in 30 seconds = 30 X 96X1000/(60X60) meters = 800 meters
        Length of the tunnel = 800 meters.

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