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A boat running downstream covers a distance of 16 km in 2 hours while for covering the same distance upstream, it takes 4 hours. What is the speed of the boat in still water?

14 km/hr
26 km/hr
38 km/hr
4Data inadequate

Answer:- 1

Explanation:-

Solution:

\begin{aligned} Rate downstream \\ = (\frac{16}{2}) k m p h = 8 k m p h . \\ Rate upstream \\ = (\frac{16}{4}) k m p h = 4 k m p h . \\ ∴ Speed in still water \\ = \frac{1}{2} (8 + 4) k m p h = 6 k m p h \end{aligned}

$\eqalign{ & {\text{Rate}}\,{\text{downstream}} \cr & = \left( {\frac{{16}}{2}} \right)kmph = 8\,kmph. \cr & {\text{Rate}}\,{\text{upstream}} \cr & = \left( {\frac{{16}}{4}} \right)kmph = 4\,kmph. \cr & \therefore {\text{Speed}}\,{\text{in}}\,{\text{still}}\,{\text{water}} \cr & = \frac{1}{2}\left( {8 + 4} \right)kmph = 6\,kmph \cr}$

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", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

\begin{aligned} Rate downstream \\ = (\frac{16}{2}) k m p h = 8 k m p h . \\ Rate upstream \\ = (\frac{16}{4}) k m p h = 4 k m p h . \\ ∴ Speed in still water \\ = \frac{1}{2} (8 + 4) k m p h = 6 k m p h \end{aligned}

$\eqalign{ & {\text{Rate}}\,{\text{downstream}} \cr & = \left( {\frac{{16}}{2}} \right)kmph = 8\,kmph. \cr & {\text{Rate}}\,{\text{upstream}} \cr & = \left( {\frac{{16}}{4}} \right)kmph = 4\,kmph. \cr & \therefore {\text{Speed}}\,{\text{in}}\,{\text{still}}\,{\text{water}} \cr & = \frac{1}{2}\left( {8 + 4} \right)kmph = 6\,kmph \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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