Question
A train can cross a pole in 6 seconds while it can cross
a 240 metres long platform in 18 seconds. Find the time (in hours) taken by the train to cover a distance of 540 km if the train increased its speed by 50%.Solution
Let speed of train is ‘x’ m/s while length of the train is ‘l’ metres.
So, l = 6x
And, l + 240 = 18x
⇒ 6x + 240 = 18x
⇒ 12x = 240
⇒ x = 20
Speed = 20 × 18/5 = 72 km/h
Increased speed = 1.5 × 72 = 108 km/h
Time = 540 / 108 = 5 hours
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