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:
282 comments Page 20 of 29.
Rakshith said:
8 years ago
Can anybody explain me why are we taking 36-20, and Why 540-300?
Please explain this step.
Please explain this step.
Vetri said:
2 decades ago
Train passes 36 sec but man standing 20sec so (36-20=16)
speed= 15m/sec
length=16*15=240m
speed= 15m/sec
length=16*15=240m
Kranthi said:
2 decades ago
As they asked only platform length why isn't it 35X15=540...
why should we substract...??
why should we substract...??
Bhatu said:
1 decade ago
Friends I think the actual answer is 540m, please tell me anybody it is correct or not?
Er.Shubham said:
8 years ago
@Krishna,
Don't compare the Length of both.
Take only the starting and ending point.
Don't compare the Length of both.
Take only the starting and ending point.
Ramya said:
7 years ago
Please explain, how come 15*20?
Length of the train means we have to do 15*36, right?
Length of the train means we have to do 15*36, right?
Noradavis said:
4 years ago
@All.
Since the train is moving toward the man you can do 36-20 seconds = 16 seconds.
Since the train is moving toward the man you can do 36-20 seconds = 16 seconds.
(8)
Aasif Javed said:
1 decade ago
@Ashwini is your calculation right?
Please check it.
x = 54*5/18*36 = 540m not 240m
Please check it.
x = 54*5/18*36 = 540m not 240m
Ani said:
8 years ago
Net time = 36-20 = 16,
So length of platform is =time * speed,
That is=16x15=240 MTR.
So length of platform is =time * speed,
That is=16x15=240 MTR.
Manonmani said:
1 decade ago
I also having doubt.
Why we took 20 sec (300=20*15).
Instead of 30sec (450=30*15).
Why we took 20 sec (300=20*15).
Instead of 30sec (450=30*15).
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