Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 18)
18.
A 300 metre long train crosses a platform in 39 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform?
Answer: Option
Explanation:
Speed = | ![]() |
300 | ![]() |
m/sec = | 50 | m/sec. |
18 | 3 |
Let the length of the platform be x metres.
Then, | ![]() |
x + 300 | ![]() |
= | 50 |
39 | 3 |
3(x + 300) = 1950
x = 350 m.
Discussion:
39 comments Page 2 of 4.
Akhila said:
7 years ago
A simple and Understandable explanation, Thanks. @Sundar.
VENU said:
7 years ago
Speed = distance/time.
so i.e 300/18 =50/3.
Let distance of pltfrm is X.
so time taken by the trn to cross platform =(X+300)/50/3 =39,
i.e X+300=(39*50)/3,
650-300=X,
X=350.
so i.e 300/18 =50/3.
Let distance of pltfrm is X.
so time taken by the trn to cross platform =(X+300)/50/3 =39,
i.e X+300=(39*50)/3,
650-300=X,
X=350.
(2)
Hemanth said:
7 years ago
In this problem, speed is not given then how to take 300/18?
(1)
Abhi said:
7 years ago
@Sundar.
Thanks For the explanation.
Thanks For the explanation.
Archana said:
8 years ago
How it's 350? I didn't understand please tell me the answer.
Amrendra mishra said:
8 years ago
Let, Length of platform being static will be-(300+x).
and, the speed of train while passing pole is -300/18=150/9.
Hence;-
150/9=(300+x)/39,
x=350 ans.
and, the speed of train while passing pole is -300/18=150/9.
Hence;-
150/9=(300+x)/39,
x=350 ans.
Chakri said:
8 years ago
The speed to cross the pole and the platform is same there is no change in speed but why we have to take 18 sec?
Nikita said:
8 years ago
Thank you @Umesh.
Masud said:
8 years ago
@Koushik Roy.
300/18 m/s, it's the speed of train.
300/18 m/s, it's the speed of train.
Akshitkumar said:
9 years ago
Tell the shortcut in detail.
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