A car travels a distance of200 km at the speed of 50 kmph. If it covers the ne×t 160 km of its journey at the speed of 80 kmph and last 80 km of its journey at the speed of 40 kmph. What is the average speed of the car?
D1= 200 Km, S1= 50 Km/hr, D2= 160 Km, S2 = 80 Km/hr, D3= 80 Km, S3= 40 km/hr. T1= (Distance )/Speed = (200 )/50 = 4 hr. T2 = (Distance )/Speed = (160 )/80 = 2 hr. T3= (Distance )/Speed = (80 )/40 = 2 hr. Average Speed= (Total Distance )/(Total Time) = (440 )/8 = 55 km/hr.
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