time speed and distance

Question

a man traveled from the village to the post office at the rate of 25 kmph and walked back at the rate of4 kmph if the whole journey took 5 hours 48 minutes find the distance of the post office from the village 

Answer 1

5 hours and 48 minutes is 5 + 4/5 = 29/5 hours.

 

Let x be the length of the trip measured in kilometers. Use t = x/v

 

It takes him x/25 hours to travel to the post office and x/4 hours to walk back and that should sum to 5.8 hours

 

x/25 + x/4 = 29/5

 

4x/100 + 25x/100 = 29/5

 

29x/100 = 29/5

 

x/100 = 1/5

 

x = 100/5 = 20

 

The post office is 20 km from the village.