Indian Institute of Foreign Trade 2016 Solved Paper

(a) According to question, Let the distance between Delhi and Noida is x km. Let they first meet at point A after one hour. Distance covered by Shruti = 2x – d Distance covered by Krishna = d ∴ Ratio of speeds of Shruti and Krishna is 2x – d : d ...(i) Let next they meet at B after half an hour. As Krishna covered distance ‘d’ in one hour, so he will cover distance $\frac{d}{2}$ in half an hour ∴ AB = $\frac{d}{2}$ Distance covered by Shruti in second meeting = $x - d + \left( x - \frac{3d}{2} \right) = 2x - \frac{5d}{2}$ ∴Ratio of speeds of Shruti and Krishna is $2x - \frac{5d}{2} : \frac{d}{2}$ ...(ii) $\frac{2x - d}{d} = \frac{2x - \frac{5d}{2}}{\frac{d}{2}} \Rightarrow 2x - d = 4x - 5d$ $\Rightarrow 2x = 4d \Rightarrow x = 2d$ Now Krishna covered distance ‘d’ in one hour, so he will cover distance between Delhi to Noida in 2 hours.