Ravi and Rajiv decided to run a 960 m long race on a track as long as the length of the race.Which of the statement(s) below is (are) sufficient to conclude that Rajiv caught up with Ravi with $$\frac{3}{8}$$​ of the track length still to be covered?

Statement 1: Ravi is allowed to start 5 seconds before Rajiv started running.

Statement 2: Ravi ran at 8 m per second.

Statement 3: Rajiv ran at a speed of 10 m/s?

Correct option is D

Given:
Length of the race: 960 meters.
Track length: Same as the race length (960 meters).
Rajiv caught up with Ravi with $$\frac{3}{8}$$​ of the track length still to be covered, i.e., when there were $$\frac{3}{8} \times 960$$​ = 360 meters remaining.
We need to determine which statement(s) are sufficient to conclude that Rajiv caught up with Ravi when there were 360 meters remaining.

Statement 1: Ravi is allowed to start 5 seconds before Rajiv started running.

Statement 2: Ravi ran at 8 m per second.

Statement 3: Rajiv ran at a speed of 10m/s?

​$$\left(\frac{5}{8}\text{of the total length}\right)$$     $$\left(\frac{3}{8}\text{of the total length}\right)$$   

Ravi covered in 5 seconds = 5 $$\times$$ 8 = 40 m

Relative speed = 10 - 8 = 2 m/s

Time taken by rajiv with relative speed = $$\frac{40}{2}$$  = 20 second

In 20 second Rajiv covered = 20 $$\times$$ 10 = 200  meter.

So, Rajiv caught Ravi at 200 meter which is not equal to 360 meters.

Therefore, Even all the three statements taken together is not sufficient.

Thus, the correct option is (d).

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