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:
494 comments Page 6 of 50.
Raghu k said:
5 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)
Bhanu Pratap said:
3 months ago
The speed of the train is x.
And the speed of the men in m/sec = 5 * 5/18.
= 25/18 m/sec.
So, time = distance/speed.
10 = 125/x-25/18.
10x - 250/18 = 125.
10x - 125/9=125.
10x = 125+125/9.
10x = 1250/9.
x = 1250/90.
x = 125/9.
The speed of the train is 125/9 m/sec.
Converting to km/hr, we get 125/9 * 18/5.
= 50 km/hr.
And the speed of the men in m/sec = 5 * 5/18.
= 25/18 m/sec.
So, time = distance/speed.
10 = 125/x-25/18.
10x - 250/18 = 125.
10x - 125/9=125.
10x = 125+125/9.
10x = 1250/9.
x = 1250/90.
x = 125/9.
The speed of the train is 125/9 m/sec.
Converting to km/hr, we get 125/9 * 18/5.
= 50 km/hr.
(8)
Priyanka devi said:
5 years ago
@Rahul.
Great work, Thanks for explaining.
Great work, Thanks for explaining.
(7)
Sonianenavath said:
1 year ago
Very Good Thanks.
(7)
Kiran said:
8 months ago
@Naveen reddy.
Why adding +5? please explain to me.
Why adding +5? please explain to me.
(7)
Moses Obia said:
5 years ago
Where was 18 got from? Please explain.
(6)
Bunny said:
5 years ago
Why the speed of the train is calculated by 125 meters by 10sec?
(6)
Supriyo Das said:
8 months ago
@Kiran.
There is x - 5 = 45 which means x = 45 + 5.
So, the result will be 50.
There is x - 5 = 45 which means x = 45 + 5.
So, the result will be 50.
(5)
Md shahrukh Ansari said:
4 months ago
Good Explanation. Thanks a lot.
(5)
Jothi said:
2 decades ago
Please explain to sutract -5 but ans is 50.
(4)
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