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.
Satya said:
7 years ago
Why is it divided by 18/5 and how it is? Please explain.
Sarang said:
7 years ago
Distance=speed * time.
In same direction speed is added,
125=speed*10,
125/10= speed,
12.5 *18/5,
45 relative speed of train,
5 + 45 = 50.
In same direction speed is added,
125=speed*10,
125/10= speed,
12.5 *18/5,
45 relative speed of train,
5 + 45 = 50.
Apoorva E said:
7 years ago
Whenever you convert speed from km/hr to m/sec you should multiply the speed by 5/18.
Vice versa when you convert m/sec to km/hr you should multiply the speed by 18/5.
Vice versa when you convert m/sec to km/hr you should multiply the speed by 18/5.
Bharat Gupta said:
7 years ago
Please explain the relative speed = (x - 5) km/hr.
Vikash gupta said:
7 years ago
Relative velocity is 125/10, how?
Suraj Kumar Swami said:
7 years ago
x-5 = 45 the result should be 40, then why it is 50?
Bouvthika R.M said:
7 years ago
Here please explain for what reason it becomes (X-5).
I can't understand.
I can't understand.
Veni balamurugan said:
7 years ago
How come 25/2? Please explain.
Subu D. said:
7 years ago
125 = speed /10.
Speed = 125/10= 25/2.
Speed = 125/10= 25/2.
Sonu kumar from bihar said:
7 years ago
@Suraj Kumar
It is X-5=45,
So, X=45+5=50.
@Bouvthika.
45km/hr is the relative speed of train w.r.t. the man running speed, but we let the actual speed of the train is X km/hr, so actual speed of train- man running speed = relative speed of the train.
It is X-5=45,
So, X=45+5=50.
@Bouvthika.
45km/hr is the relative speed of train w.r.t. the man running speed, but we let the actual speed of the train is X km/hr, so actual speed of train- man running speed = relative speed of the train.
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