Question

A MAN GOES TO TOWN AT 40 KM PER HOUR AND COMES BACK AT 60 KM PER HOUR.WHAT IS THE AVERAGE SPEED

Answer 1

Let the distance between town and house be X km. 

TIme taken to reach the town :  X/40 hours
Time taken to come back home  : X/60 hours

Total time of travel : X(3+2)/120  = X/24 hours

Average speed = Total distance / total time = 2 X / (X/24) = 48 kmph 

Answer 2

let the distance between house and town be x 
so time taken to go to town = x/40
and time taken to reach home = x/60 
Total distance = x+  x = 2x
So average velocity is distance/time
                            
$\frac{2X}{\frac{X}{40}+\frac{X}{60}}$

= 48 kmhr⁻¹