A boat can tarvel 36 km upstream in 5 hours. If the speed of the stream is 2.4 kmph, how much time will the boat take to cover a distance of 78 km downstream?(in hours)
A. 5 hours
B. 6.5 hours
C. 5.5 hours
D. 8 hours
Answer: Option B
Solution(By Examveda Team)
Distance covered by a boat in 5 hours = 36 kmRate upstream of boat = $$\frac{{36}}{5}$$ = 7.2 kmph
Speed of the stream = 2.4 kmph
∴ Speed of the boat in still water
= (7.2 + 2.4) kmph
= 9.6 kmph
∴ Rate downstream of the boat
= (9.6 + 2.4) kmph
= 12 kmph
∴ Time taken in covering 78 km distance
= $$\frac{{78}}{{12}}$$
= 6.5 hours
Related Questions on Boats and Streams
A. 2 hours
B. 3 hours
C. 4 hours
D. 5 hours
E. None of these
A. 8.5 km/hr
B. 9 km/hr
C. 10 km/hr
D. 12.5 km/hr
E. None of these
A. 2 : 1
B. 3 : 2
C. 8 : 3
D. Cannot be determined
E. None of these
A. 4 km/hr
B. 5 km/hr
C. 6 km/hr
D. 10 km/hr
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