Question
A train can cross a pole in 48 seconds. While if the
train increased its speed by 50% then time taken by it to cross 225 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 = 48 × x = 48x metres And, 48x + 225 = 1.5 × x × 42 Or, 15x = 225 Or, x = 15 m/s So, length of train = 48 × 15 = 720 metres Desired time = (720 + 120)/15 = 56 seconds
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