Question

A body travel a distance of 10 km with a constant speed of 30km /h^-1 and then next 40km at a constant speed of 50km^-1 . Find the average speed for the whole journey .

Answer 1

Answer:

D1=10 km.  

T1=10/30=1/3hr.

D2=40km.

T2=40/50=0.8hr

Average speed=d1+d2/t1+T2

10+40/1/3+0.8=45.4km/hr