document.write( "Question 23019: I know there's a similar problem, but got very confused by the way the set-up was formatted in the response. Can someone pllleeeeease help? All I need is to see which numbers & variables go where, then I should be able to solve it. Thanks in advance!\r
\n" ); document.write( "\n" ); document.write( "In still water a boat can travel 15 mph. It travels 36 miles upstream & 36 miles downstream in a total time of 5 hours. Find the speed of the current. (The book says the answer is 3 mph) \n" ); document.write( "
Algebra.Com's Answer #11405 by stanbon!(97)\"\" \"About 
You can put this solution on YOUR website!
Use d=rt in he form t=d/r
\n" ); document.write( "Let the current speed be represented by \"c\".
\n" ); document.write( "Upstream Data:
\n" ); document.write( "d=36; rate= 15-c; therefore time upstream = 36/(15-c)
\n" ); document.write( "Downstream Data:
\n" ); document.write( "d=36; rate = 15+c; therefore time downstream = 36/(15+c)
\n" ); document.write( "EQUATION:
\n" ); document.write( " Time up + Time down = 5 hrs
\n" ); document.write( " 36/(15-c) + 36/(15+c) = 5
\n" ); document.write( " 1/(15-c) + 1/(15+c) = 5/36
\n" ); document.write( " 30/(225-c^2) = 5/36
\n" ); document.write( " 6/(225-c^2) = 1/36
\n" ); document.write( " 6(36) = 225-c^2
\n" ); document.write( " -c^2 = -9
\n" ); document.write( " c = 3 mph (speed of current)\r
\n" ); document.write( "\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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