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Shail rai

Dec 30, 2013

A train travels a distance of 480 km at a uniform speed.

A train travels a distance of  480 km at a uniform speed. If the the speed had been 8 km/h less, then it would have taken 3 hours more to cover the same distance. We need to find the speed of the train.

Answers(2)

Answer

Agam Gupta

Distance travelled by the train = 480 km
Let the speed of the train be x kmph
Time taken for the journey = 480/x
Given speed is decreased by 8 kmph
Hence the new speed of train = (x – 8) kmph
Time taken for the journey = 480/(x – 8)�

1280 = x2�– 8x
�x2�– 8x – 1280 = 0
On solving we get x = 40
Thus the speed of train is 40 kmph

Kishore Kumar

Distance travelled by the train = 480 km
Let the speed of the train be x kmph
Time taken for the journey = 480/x
Given speed is decreased by 8 kmph
Hence the new speed of train = (x – 8) kmph
Time taken for the journey = 480/(x – 8) 

1280 = x2 – 8x
 x2 – 8x – 1280 = 0
On solving we get x = 40
Thus the speed of train is 40 kmph
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