Vinod travelled from his home to his office at a speed of 20 km/h and walked back at a speed of 5 km/h. The whole journey took 4 h. The distance between his office and his home is:

Correct option is C

Given:

Speed while going = 20 km/h
Speed while returning = 5 km/h
Total time for the journey = 4 hours

Formula Used:

Time = $$\frac{\text{Distance} }{\text{ Speed}}$$​

Solution:

Let the one-way distance = x km

​$$\frac{x}{20} + \frac{x}{5} = 4$$​​

​$$\frac{x + 4x}{20} = 4$$​​

$$\frac{5x}{20} = 4$$​

x = 16

The distance between Vinod's home and office is 16 km.