Question

a motorcyclist drives from A to B with uniform speed of 30 metre per second and returns with a speed of 20 km per hour find his average speed​

Answer 1

Explanation:

s1=30m/s

s2=58.33m/s

s1-s2÷100=29.4167m/s

Answer 2

Let the distance be x

while going........

d=xkm

speed=30km/hr

time=d/s=x/30

while coming........

d=x

speed=20km/hr

time=x/20

now,avg speed=total distance /total time 

                         =x+x/x/20+x/30

                         =2x/5x/60

                         =2*12

               =24km/hr