A train covers a certain distance at a uniform speed. If the train had been 8 kilometre per hour fas

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27 Jan 2022 Time Distance & Speed

A train covers a certain distance at a uniform speed. If the train had been 8 kilometre per hour faster, it would have taken 3 hour less than the scheduled time and if the train was slower by 8 kilometre per hour it would have taken 5 hour more than the schedule time. Find length of the journey.

OPtion

1) 620
2) 540
3) 480
4) 650
5) 720
6) 630
7) 420
8) 384
9) 360
10) None of these

Solution

Let the speed of the train be 'x' km/h and the time taken by train to travel the given distance be 't' hours and the total distance be 'd' km. We know that, Distance=Speed*Time​
.'. d=x*t
According to 1st case: (x+8)*(t-3) = d
-3x + 8t = 24 ------(1)
Similarly, according to 2nd case: (x-8)*(t+5) = d
5x - 8t = 40 ----(2)
Solving eqn. (1) & (2), we get x=32, t=15
Hence, total length of the journey = d = x*t = 32*15 = 480 km.

Correct Option: 3 Best Solution (0)