<PRE><B>Question 965093</B>
In still water, Jacob&#39;s sailboat cruises at 16.5 km/h. On the river near their cottage, the boat travels faster downstream than upstream, because of the current. The boat takes 5 hours for a trip upstream but only 2 hours to do the same distance on the return downstream. Determine the speed of the current by jacobs cottage.
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let c=speed of current
16.5+c=speed of sailboat downstream
16.5-c=speed of sailboat upstream
travel time*speed=distance
..
2(16.5+c)=5(16.5-c)
33+2c=82.5-5c
7c=49.5
c=7.07 km/h</PRE>