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?

• A. $6seconds$
• B. $7seconds$
• C. $7.5seconds$
• D. $6.5seconds$

Answer 1

The correct option is C $7.5seconds$



Time taken to cross the electric pole = 3 seconds.

Distance covered to cross electric pole

= length of the train = 110m.

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

$\Rightarrow 110x=275\times 3$

$\Rightarrow =\frac{\text{/}{275}^{55}\times 3}{\text{/}{110}_{22}}=\frac{\text{/}{55}^5\times 3}{\text{/}{22}_2}$

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