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:
287 comments Page 29 of 29.
Manikandan said:
6 years ago
From the given data, we can consider the only man as a reference point to find the length of train. So let us consider man is standing at the beginning, so 15*20 will be enough to find the length of the train, Am I right?
Aniket Masalkhamb said:
5 years ago
You can multiply 15 * 36 which gives you 540m then x be the length of the platform therefore as speed = distance upon time 540 +x/20 = 15.
x = 240m.
x = 240m.
Jai said:
5 years ago
t1-t2 = 36 - 26 = 16.
We know 54 x 5/18=15,
So putting in formula s=d/t.
15 = d/16, where d is taken as length here;
d = 15 * 16,
= 240.
We know 54 x 5/18=15,
So putting in formula s=d/t.
15 = d/16, where d is taken as length here;
d = 15 * 16,
= 240.
Keerthi said:
5 years ago
Why we, not multiple 15 * 36 instead we multiple 15 * 20? Please explain.
Sharath Naik said:
5 years ago
Why they have taken 20 sec. Can we take 30 sec also? Please explain.
Vishakha said:
3 months ago
I think if we multiply speed with time of platform then it is 540.
Anom said:
2 weeks ago
Nice explanation. Thanks to all for clarifying the answer.
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