document.write( "Question 1012151: A boat can travel 16 kilometers per hour in still water. The boat travels 15 kilometers down a river and then 15 kilometers upstream. The entire trip takes 5.5 hours. What is the equation that describes the current,c, of the river?
\n" ); document.write( "A) ((5.5)/(15+c))+((5.5)/(15-c))=16
\n" ); document.write( "B) ((5.5)/(16+c))+((5.5)/(16-c))=15
\n" ); document.write( "C) ((16)/(15+c))+((16)/(15-c))=5.5
\n" ); document.write( "D) ((15)/(16+c))+((15)/16-c))=5.5\r
\n" ); document.write( "\n" ); document.write( "***I believe the answer is c but I want to make sure because i had trouble figuring it out*** Please help \n" ); document.write( "

Algebra.Com's Answer #628003 by Boreal(15235) $\"\"$ $\"About$

You can put this solution on YOUR website!
c=current
\n" ); document.write( "trip downstream is 15 miles at (16+c) mph=15/(16+c) hr
\n" ); document.write( "trip upstream is 15 miles at (16-c) mph=15/(16-c) hr
\n" ); document.write( "Those two equal 5.5
\n" ); document.write( "It is D.
\n" ); document.write( "Multiply everything by (16+c)(16-c)
\n" ); document.write( "240-15c+240+15c=1408-5.5c^2
\n" ); document.write( "5.5c^2-928=0
\n" ); document.write( "The current is about 13 km/h
\n" ); document.write( "downstream at 29 km/h (about) takes just under a half hour.
\n" ); document.write( "upstream at 3 km/h takes about 5 hours.\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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