Question

A person goes to a certain place at the speed 4kmph. he returns on bicycle at the speed of 16 kmph. find his average speed during the whole journey?

Answer 1

His average speed = 2v1v2/v1 + v2 

= (2 x 4 x 16)/ 4 + 16 = 128 / 20 = 6.4 km/h 

hence , you got the answer as 6.4km/h