Question

A train takes 3 seconds to cross an electric pole. If the length of the train is 110m, then how long will the train take to cross a platform which is of length 165m [4 MARKS]

Answer 1

Concept: 1 Mark
Application: 3 Marks


Time taken to cross the telegraph pole = 3 seconds.

Distance covered to cross telegraph pole

= length of the train = 110 m.

Now, the distance covered by the train to cross a railway platform

= 110 + 165

= 275 m

$\begin{array}{cc}Distance& Time\\ 110& 3\\ 275& x\end{array}$

This is a case of direct variation

$\Rightarrow \frac{110}{3}=\frac{275}{x}$

$\Rightarrow x=\frac{275\times 3}{110}=\frac{55\times 3}{22}$

$=\frac{15}{2}=7.5seconds$