Question

A car travelles 30km in a uniform speed of 40km/hr and the next 30 km at a uniform speed of 20km/hr. Find the average speed.

Answer 1

time for first journey =distance/speed
=30/40=3/4hr=0.75hr
time for second journey =30/20=3/2hrs=1.5hr
average speed= total distance/ total time
60/2.25=26.667km/hr