Question

A motorcyclist drives A and B with uniform speed of 30 kmph and return backs with a speed of 20 kmph. Find average speed

Answer 1

Let the distance from A to B be z

While going; v=30km/h

                     s=(z)km

                     t= s/v = (z/30)h

While returning, v=20km/h

                           s=(z)km

                            t= (z/20)h

Therefpre average speed=

(z+z)km / (z/30+z/20)h

=24km/h