Infosys Company Numerical Ability Time Distance and Speed

A train ran at a certain speed for one hour and then due to a technical problem, it ran at 3/5th of its original speed and reached the destination 2 hrs late. The driver said, had the problem occurred 50 miles later, we would have gained 40 minutes. What is the distance between the two cities that the train traveled?

Read Solution (Total 1)

In this question, we have to solve for original time and original speed and then we will calculate the total distance.

Let v & t be the speed & time respectively.
Therefore, total distance=vt mile

FIRST CASE:
(1 hour + time taken to travel after problem) = (original time + 2 hours)
=> 1+ (vt-v)/(3v/5) = t+2
=> (5t-5)/3 = t+1
=> 5t-5 = 3t+3
=> 2t = 8
=> t=4 hour

SECOND CASE:
distance travelled in 1 hour = v*1 mile
i.e. total time taken to travel the journey of vt mile = ( (v+50)/v + (vt-(v+50))/3v/5)
according to question if problem would have occurred after 50 mile then driver would have saved 40 min
=> (t+2) - ( (v+50)/v + (vt-(v+50))/3v/5) = 40/60
=> 6 - (18v-100)/3v = 2/3
=> 18v-18v+100 = 2v
=> 2v = 100
=> v=50 mile/hour

distance = vt = 50*4 = 200 miles

Thus, we have time=4 hour and speed=50mile/hour
Hence total distance= 4*50 mile = 200 mile
Ans 200 miles
10 years agoHelpfull: Yes(5) No(0)

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