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A man takes 2.2 times as long to row a distance upstream as to row the same distance downstream. If he can row 55 km downstream in 2 hours 30 minutes. what is the speed of the boat in still water ? (in km/ h)

A) 40
B) 8
C) 16
D) 24

Correct Answer:



C) 16

Description for Correct answer:
Rate downstream = \( \Large \frac{55}{\frac{5}{2}} \)

= \( \Large \frac{55 \times 2 }{5} = 22 kmph \)

Time taken in upstream journey

= \( \Large (\frac{5}{2} \times 2.2) hours \)

= 5.5 hours

\( \Large \therefore Rate upstream = \frac{55}{5.5} \)

= 10 kmph

\( \Large \therefore \) Speed of boat in still water

= \( \Large \frac{1}{2} (22 + 10) \)

= \( \Large \frac{1}{2} \times 32 = 16 \ kmph \)

Part of solved Aptitude questions and answers : >> Aptitude

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Similar Questions

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C). 2 hrs 40 mins

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