Question

Ramesh reaches his destination on time by travelling at 40 kmph. He covered two-third the total distance in one-third of the total time. What speed should he maintain for the remaining distance to reach his destination on time?
1. 10 km/hr 
2. 5 km/hr 
3. 20 km/hr
4. 30 km/hr 
5. None of these 

Answer 1

Correct Answer - Option 3 : 20 km/hr

Given:

Reaches destination on time when speed = 40 km/hr

Formula:

Speed = distance/time

Calculations:

Let the time taken to reach the destination be 3x hours.

Total distance = 40 × 3x = 120x km

He covered 2/3 × 120x = 80x km in 1/3 × 3x = x hours

So, the remaining 40x km, he has to cover in 2x hours

Required speed = 40x/2x = 20 kmph

∴ Required speed to reach destination on time is 20 km/hr