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 5 of 48.
Rahul agrawal said:
2 years ago
125 m = 10sec
Than 60sec = 125 x 6 = 750m
1hour = 750 x 60 = 45000m (45km/hr) + 5km/hr = 50km/hr.
Than 60sec = 125 x 6 = 750m
1hour = 750 x 60 = 45000m (45km/hr) + 5km/hr = 50km/hr.
(60)
Mohammed Asif said:
3 years ago
The speed of train is 45 km per hour
And relative speed is 50 km per hour.
But in the question only speed of train is asked not the relative speed.
So, please either change the question and mention relative speed or change the answer to option A 45 km per hour which is the speed of train.
And relative speed is 50 km per hour.
But in the question only speed of train is asked not the relative speed.
So, please either change the question and mention relative speed or change the answer to option A 45 km per hour which is the speed of train.
(37)
Osaji Jeff said:
3 years ago
Why was the formula reversed from 5/18 to 18/5? Please explain me.
(29)
Iliyas said:
3 years ago
m/sec = [1/1000 km] / [1/3600 sec]
= [1/1000] *[3600/1],
= [3600/1000].
= [18/5]km/hr.
= [1/1000] *[3600/1],
= [3600/1000].
= [18/5]km/hr.
(28)
Priyanka devi said:
4 years ago
@Rahul.
Great work, Thanks for explaining.
Great work, Thanks for explaining.
(7)
Bunny said:
4 years ago
Why the speed of the train is calculated by 125 meters by 10sec?
(6)
Moses Obia said:
4 years ago
Where was 18 got from? Please explain.
(6)
Raghu k said:
4 years ago
It is simple guys.
If we observe hint, her there should be the relative speed because the train and are travelling in the same direction so we (train) -v (man) T =Distance.
(120/10) (18/5) =v (t) -5.
45+5=v (t).
50=v (t).
If we observe hint, her there should be the relative speed because the train and are travelling in the same direction so we (train) -v (man) T =Distance.
(120/10) (18/5) =v (t) -5.
45+5=v (t).
50=v (t).
(8)
Kushal M V said:
4 years ago
They took 18/5 because the length of train is in meter and time given which passes the man is given in seconds. To convert m/s to km/ hr they multiplied with 18/5. And the answers also in km/hr.
(2)
Kushal M V said:
4 years ago
They took 18/5 because the length of train is in meter and time given which passes the man is given in seconds. To convert m/s to km/ hr they multiplied with 18/5. And the answers also in km/hr.
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