A bus travels the first 20 km at 40 km/h and the next 20 km at 60 km/h. Average speed is MCQ with Answer and Explanation

A bus travels the first 20 km at 40 km/h and the next 20 km at 60 km/h. Average speed is
A. 50 km/h
B. 52 km/h
C. 45 km/h
D. 48 km/h
Answer: Option D
Solution (By JKSSB Mock Tests)
Time1 = 20/40=0.5 h, Time2=20/60=1/3 h. Total time=5/6 h. Total distance=40 km. Avg speed=40/(5/6)=48 km/h. Not arithmetic mean.

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