Question

The length of a train and that of a platform are equal. If with a speed of $90$ km/hr, the train crosses the platform in one minute, then the length of the train (in metreis :

• A. $500$ m
• B. $600$ m
• C. $750$ m
• D. $900$ m

Answer 1

The correct option is C $750$ m

Let the length of the train and platform be $x$ mt.

$\therefore$ Distance covered by the train as it cross the platform $=x+x=2x$ mt

It does so in $1$ min $=60$ sec.

and the speed $=90$ km/hr $=90\times \frac{5}{18}$ m/sec $=25$ m/sec

$\therefore$ Distance $=$ Speed $\times$ time

$\Rightarrow 2x=25\times 60$

$\Rightarrow x=25\times 30=750m$

Answer : Option C.