Question
A train crosses a 250-metre-long platform in 18 seconds,
and a tunnel 60% longer than the platform in 27 seconds. Find the speed of train in km/h.Solution
Let the length and speed of train be ‘l’ metres and ‘x’ m/s, respectively.
Then, according to question,
(l + 250)/18 = (l + 400)/27
3l + 750 = 2l + 800
l = 50
l = 50 metres
x = (l + 250)/18 = 300/18 ×(18/5) = 60 km/h
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