Question

The average speed of a train is 20% less

on the return journey than on the onward

journey. The train halts for half an hour at

the destination station before starting on

the return journey. If the total time taken

for the to and fro journey is 23 hours,

covering a distance of 1000 km, the speed

of the train on the return journey is

Answer 1

Train was halted for half an hour.
So, total time taken in Journey = 23 - (1/2) = 22.5 hours.
Average speed in Whole Journey = 1000/22.5 = 44.5 km/hr.
The average speed on return journey is 20% less than onward journey.
Therefore, ratio of average speed of onward and return journey,
= 100/80 = 5/4.
Let average speed of onward journey = 5x.
Average speed on return journey = 4x.
Average speed on whole journey = (5x +4x)/2
44.5 = (5x + 4x)/2
89 = 9x
x = 9.88.
Average speed on return = 9.88 *4 = 39.52 = 40 kmph (Approx.)

Answer 2

Answer:

The Train was halted for half an hour.

So, total time during Journey = 23 - (1/2) = 22.5 hours.

Average speed in Whole Journey = 1000/22.5 = 44.5 km/hr.

The average speed on return journey is 20% less than onward journey.

Therefore, ratio of average speed of onward and return journey,

= 100/80 = 5/4.

Let average speed of onward journey = 5x.

Average speed on return journey = 4x.

Average speed on whole journey = (5x +4x)/2

44.5 hour = (5x + 4x)/2

89 = 9x

x = 9.88.

Average speed on return = 9.88 *4 = 39.52 = 40 km/h (Approximately.)

Step-by-step explanation: