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A motorboat takes 2 hours to travel a distance of 9 km down the current and it takes 6 hours to travel the same distance against the current. What is the speed of the boat in still water in kmph?


A) 3

B) 2

C) 1.5

D) 1

Correct Answer:
A) 3

Description for Correct answer:
Let the speed of boat in still water and speed of current are x and y km/h respectively.

Therefore Downward speed of boat = (x+y) km/h.

According to question,

\( \Large x + y = \frac{9}{2} = 2x + 2y = 9 \) ...(i)

and \( \Large x - y = \frac{9}{6} = 2x - 2y = 3 \) ...(ii)

On solving equations (i) and (ii), we get

x = 3, y = \( \Large \frac{3}{2} \)

Part of solved Boat and Stream questions and answers : >> Aptitude >> Boat and Stream




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