document.write( "Question 916705: A kayak can travel 18 miles downstream in 3 hours, while it would take 9 hours to make the same trip upstream. Find the speed of the kayak in still water as well as the speed of the current. \n" ); document.write( "
Algebra.Com's Answer #556237 by lwsshak3(11628)\"\" \"About 
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A kayak can travel 18 miles downstream in 3 hours, while it would take 9 hours to make the same trip upstream. Find the speed of the kayak in still water as well as the speed of the current.
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\n" ); document.write( "let x=speed of kayak in still water
\n" ); document.write( "let c=speed of current
\n" ); document.write( "x+c=speed of kayak downstream
\n" ); document.write( "x-c=speed of kayak upstream
\n" ); document.write( "travel time*speed=distance
\n" ); document.write( "..
\n" ); document.write( "3(x+c)=18
\n" ); document.write( "9(x-c)=18
\n" ); document.write( "..
\n" ); document.write( "3x+3c=18
\n" ); document.write( "9x-9c=18
\n" ); document.write( "..
\n" ); document.write( "9x+9c=54(mult. eq by 3)
\n" ); document.write( "9x-9c=18
\n" ); document.write( "add
\n" ); document.write( "18x=72
\n" ); document.write( "x=4
\n" ); document.write( "3c=18-3x=18-12=6
\n" ); document.write( "c=2
\n" ); document.write( "speed of kayak in still water=4 mph
\n" ); document.write( "speed of current=2 mph \n" ); document.write( "
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