Dixit covers a certain distance by car, driving at the speed of 28km/h and he returns to the starting point riding on a scooter at the speed of 36km/h. Find the average speed (in km/h) for the whole journey.

Since the distance covered in both directions is the same, we can use the formula for average speed:
Average Speed=
x+y
2xy
​

Where:

x=28km/h (speed while going)

y=36km/h (speed while returning)

Substituting the values:

Average Speed=
28+36
2×28×36
​

Average Speed=
64
2×28×36
​

Average Speed=
32
28×36
​

Average Speed=
8
7×36
​
=
2
7×9
​
=
2
63
​
=31.5km/h
Therefore, the average speed for the whole journey is 31.5km/h.