Question
A train can cross a pole in 36 seconds. While if the
train increased its speed by 50% then time taken by it to cross 324 metres long platform is 42 seconds. Find the time taken by the train to cross a 120 metre long tunnel.Solution
Let speed of train is ‘x’ m/s So, length of train = 36 × x = 36x metres And, 36x + 324 = 1.5 × x × 42 Or, 27x = 324 Or, x = 12 m/s So, length of train = 36 × 12 = 432 metres Desired time = (432 + 120)/12 = 46 seconds
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