Distance-Speed-Time: Anand and Bhim take a trip

To find how long do Anand and Bhim spend driving on the first leg

Let 'd' be the distance from starting point to the destination and they are driving at 80 km/h4

=> Speed * Time = Distance

=> 80 * t = d

=> \(t = \frac{d}{80}\)

So if we can find the value of 'd' we get the value of 't'

Statement 1

Their average speed for the entire trip is 70 km per hour.

Average speed = \(\frac{Total distance}{Total time}\)

=> 70 = \(\frac{d}{(t + 4)}\)

=> 70 = \(\frac{d}{(d/8 + 4)}\)

From above equation, we get the value of d and hence the value of 't'

Statement 1 is sufficient

Statement 2

The distance to their destination is 240 km.

=> d = 240 and hence we can get the value of 't'

Statement 1 is sufficient alone
Statement 2 is sufficient alone

Hence option D