A car moves for half of its time at 80km/hr and for rest half of time at 40km/hr.The total distance covered is 60km.What is the average speed of the car?

Answer 1

time t at 80
time t at 40

80 t + 40 t = 60
120 t = 60
t = (1/2) hour at each speed

distance = 80(1/2) + 40(1/2) = 60km

av speed = 60 km/1 hour