One third of a certain journey is covered at the rate of 25 km/hr, one forth at the rate of 30 km/hr and the rest at 50 km/hr. The average speed for the whole journey is :
A. 35 km/hr
B. $$33\frac{1}{3}$$ km/hr
C. 30 km/hr
D. $$37\frac{1}{12}$$ km/hr
Answer: Option B
Solution(By Examveda Team)
Let the total distance = 1200 km$$\eqalign{ & {\text{Total time taken :}} \cr & = \frac{{400}}{{25}} + \frac{{300}}{{30}} + \frac{{500}}{{50}} \cr & = {\text{ }}16 + 10 + 10 \cr & = {\text{ 36 hours}} \cr & \therefore {\text{Average speed}} \cr & = \frac{{{\text{Total distance }}}}{{{\text{Total time}}}} \cr & = \frac{{1200}}{{36}} \cr & = 33\frac{1}{3}{\text{ km/hr}} \cr} $$
Related Questions on Speed Time and Distance
A. 48 min.
B. 60 min.
C. 42 min.
D. 62 min.
E. 66 min.
A. 262.4 km
B. 260 km
C. 283.33 km
D. 275 km
E. None of these
A. 4 hours
B. 4 hours 30 min.
C. 4 hours 45 min.
D. 5 hours
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