Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 2)
2.
A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is:
Answer: Option
Explanation:
| Speed of the train relative to man = |  |
125 |  m/sec |
| 10 |
| = | |
25 | m/sec. |
| 2 |
| = | |
25 | x | 18 | km/hr |
| 2 | 5 |
= 45 km/hr.
Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr.
x - 5 = 45 
x = 50 km/hr.
Discussion:
475 comments Page 35 of 48.
Sushanth ratan said:
8 years ago
@Jothi.
-5 if it goes on the other side it becomes plus (+).
-5 if it goes on the other side it becomes plus (+).
Ajay said:
8 years ago
As per my calculation, 50 km/hr is the right answer.
Nishant said:
8 years ago
But it should have been given that we have to find the relative velocity of the man. So, 45km/hr should be the right answer.
Priyanka said:
8 years ago
Why we consider v=5 to subtract u - v?
Venkatesh said:
8 years ago
Thank you @Nagapriya.
Ganga said:
8 years ago
Why we subtract (x-5)?
Shailesh Hiremath said:
8 years ago
So, kilometre & minutes will be calculated as 1 km=1000 mtrs and 60 minutes =3600 seconds.
If you divide 3600/1000 = 5/18.
If you divide 3600/1000 = 5/18.
Sunil said:
8 years ago
Thank you all for the given explanations.
Basava g said:
8 years ago
First, we find total length to across moving man=125+((5*10^3)÷(3600))*10.
= 125+13.888.
= 138.88m.
The speed of train = total/time.
= 138/10,
= 13.88m/s.
This one convert into km/hrs.
= 13.88 * 3600,
= 50km/hrs.
= 125+13.888.
= 138.88m.
The speed of train = total/time.
= 138/10,
= 13.88m/s.
This one convert into km/hrs.
= 13.88 * 3600,
= 50km/hrs.
Manjunath said:
8 years ago
Hi, anyone please explain to me why we should take 5/18?
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