Aptitude - Problems on Trains - Discussion

speed=distance/time.so speed=125/10.....25/2*18/5=45... the question is same direction=x-5=45 x=50

Why 125 is divided by 10?

@kumar
cause speed=distance/time

How it is 3600/1000. It will come as 1000/3600 only. Please explain.

hai raghu, in the question man's speed is given in km/hr so we gonna convert train's speed to km/hr which is actually in m/s
1 m/s = 3600 km/1000 hr
125/10 m/s= (125/10)*(3600/1000)

Hai fnds.

Howz the 12.5 is converted into 25.

Please explain.

Hi Tahira,

You just cancel 125/10 using multiples of 5.

125/10=25/2=12.5.

Ramesh chandran.

CLEAR explanaTION. THANKS.

NICE EXPLANATION ABHISHEK.

Hi friends,the problem is very simple.Think in this way.Assume that the man is not moving(standing like a pole),now findout the speed of the train using the data.
LENGTH OF THE TRAIN=125m.
TIME TAKEN BY THE TRAIN TO CROSS THE MAN(assume standing)=10sec
w k t velocity=distance(length of the train)/time.
v=(125/10)m/s
v=(25/2)m/s
convert m/s into km/hr
v=(25/2)* (3600/1000) or (25/2)*(18/5)
v=45 km/hr
45 km/hr is the train speed if the person is standig(not moving).
But in the problem person is moving and that to he is moving in the same direction in which train going,so that's y add the speed of the man to the speed of the train then we will got the correct answer.
speed of the train+speed of the man=45+5=50 km/hr.