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The time taken by a boat to travel a distance downstream is half the time taken by it to travel the same distance upstream. What is the speed of the boat downstream if it travels 7.5 km upstream in 1 hour 30 minutes ? (in km/h)

A) 7.5
B) 5
C) 9
D) 10

Correct Answer:




D) 10

Description for Correct answer:
Time taken in covering 7.5 km upstream = \( \Large \frac{3}{2} \ hours \)

\( \Large \therefore \ Time \ taken \ in \ covering \ 7.5 km \ downstream = \frac{3}{4} \ hours \)

\( \Large Speed = \frac{Distance}{Time} \)

\( \Large \therefore \) Rate downstream of boat

= \( \Large \frac{7.5}{\frac{3}{2}} = (\frac{7.5 \times 2}{3}) kmph \)

= 5 kmph

Rate downstream of boat

= \( \Large \frac{7.5 \times 4}{3} \) = 10 kmph

Part of solved Aptitude questions and answers : >> Aptitude

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Similar Questions

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