SSC Sample Paper Mock Test-6 SSC CGL Tear-II Paper-1

A moving train crosses a man standing on a platform and a bridge 300 m long in 10 s and 25 s respectively. What will be the time taken by the train to cross a platform 200 m long?

A) \[16\frac{2}{3}\,\,\text{s}\]

B) 18 s

C) 20 s

D) 22 s

Correct Answer: C

Solution :

Let the length of the train = x m

When a train crosses a platform, the distance covered

= Length of (Train \[+\] Platform)

According to the question,

Speed of train \[=\frac{x}{10}=\frac{x+300}{25}\]

\[\Rightarrow \] \[25x=10x+3000\]

\[\Rightarrow \] \[15x=3000\]

\[\Rightarrow \] \[x=\frac{3000}{15}=200\,\,m\]

\[\therefore \] Length of train \[=200\,\,m\]

Speed of train \[=\frac{x}{10}=\frac{200}{10}=20\,\,m/s\]

\[\therefore \] Time taken in crossing a 200 m long platform

\[=\frac{200+200}{20}=20\,\,s\]