A motorcyclist drives from A to B with a uniform speed of \(50\ km\ h^{-1}\) and returns back with a speed of \(20\ km\ h^{-1}\). Find its average speed.
 
The formula to calculate the average speed is,
Average speed \(=\)  \(Km\ h^{-1}\) 
Important!
Note: Enter your answer with two decimal digits.