Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 5)
5.
A train passes a station platform in 36 seconds and a man standing on the platform in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?
Answer: Option
Explanation:
| Speed = |  |
54 x | 5 |  m/sec = 15 m/sec. |
| 18 |
Length of the train = (15 x 20)m = 300 m.
Let the length of the platform be x metres.
| Then, | x + 300 | = 15 |
| 36 |
x + 300 = 540
x = 240 m.
Discussion:
276 comments Page 11 of 28.
Shro said:
1 decade ago
@ Rahul Nicely explained ...thank you :)
Abhishek said:
1 decade ago
But we don't know where man is standing on the platform. Do we ?
And if we don't know that then how do we supposed to do 15x20= 300 ?
Can anyone tell me that. ?
And if we don't know that then how do we supposed to do 15x20= 300 ?
Can anyone tell me that. ?
Shro said:
1 decade ago
@Abhishek here we are supposed to find the length of the platform.
once we find the speed of train that is 15msec.
length or distance=speed * time
so length of train = speed of train is 15m/s multiplied by the train taking time to cross the man's position in 20secs.
so= 15 * 20
If u calculate in this way ,then as per the mathematics , u will come to know where the man is standing....
In such cases Solve as per the formulas.
Hope u got it :)
once we find the speed of train that is 15msec.
length or distance=speed * time
so length of train = speed of train is 15m/s multiplied by the train taking time to cross the man's position in 20secs.
so= 15 * 20
If u calculate in this way ,then as per the mathematics , u will come to know where the man is standing....
In such cases Solve as per the formulas.
Hope u got it :)
Shakya said:
1 decade ago
You can take this question as:-
A train can pass a station platform in 36 seconds and it can pass a man standing somewhere not only on platform (this statement shows the point is stationary) in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?
speed=15 m/s
train length=15*20;
train length + platform length= 15*36=540;
platform length = 540 - train length;
platform length = 240 m (answer)
A train can pass a station platform in 36 seconds and it can pass a man standing somewhere not only on platform (this statement shows the point is stationary) in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?
speed=15 m/s
train length=15*20;
train length + platform length= 15*36=540;
platform length = 540 - train length;
platform length = 240 m (answer)
Veeresh said:
1 decade ago
xkmph means train goes x meters in 3.6 seconds. here 36-20secs required to travel for the train to pass platform.
3.6 sec---->54 meters
16 secs---->?
16/3.6x54=240 meters
3.6 sec---->54 meters
16 secs---->?
16/3.6x54=240 meters
Sudhapriya said:
1 decade ago
Thank you vetri. I gained answer from you.
Praveen prabhakar said:
1 decade ago
Distance=speed*time
Distance=(54*5/18)*(36-20)=240m
Distance=(54*5/18)*(36-20)=240m
Prakash ranjan naik said:
1 decade ago
Train speed=15m/s
Time=20s
If train pass man means,that is the tme of train
That's why
Length of train=15x20
Time=20s
If train pass man means,that is the tme of train
That's why
Length of train=15x20
Ravinder Kumar said:
1 decade ago
The simple method is
Train speed is 54km/h*5/18=15m/second
Time taken between man standing on platform and station platform ( 36-20) = 16 sec.
Distance= 15*16 = 240m
Train speed is 54km/h*5/18=15m/second
Time taken between man standing on platform and station platform ( 36-20) = 16 sec.
Distance= 15*16 = 240m
Gopu said:
1 decade ago
Simple method;.
Convert train speed into m/sec=54*5/18.
=15m/s.
Subtract train time which it had taken to cross a man from the time taken by train to cross the platform i.e,
= (36-20).
=16.
Now apply formula of distance i.e. speed*time.
=15*16.
=240. ) ).
Convert train speed into m/sec=54*5/18.
=15m/s.
Subtract train time which it had taken to cross a man from the time taken by train to cross the platform i.e,
= (36-20).
=16.
Now apply formula of distance i.e. speed*time.
=15*16.
=240. ) ).
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