document.write( "Question 388652: 19. A motorboat can go 16 miles downstream on a river in 20 minutes. It takes 30 minutes for this boat to go back upstream the same 16 miles.Let x = the speed of the boat.
\n" ); document.write( "Let y = the speed of the current.\r
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\n" ); document.write( "\n" ); document.write( "a. Write an equation for the motion of the motorboat downstream.
\n" ); document.write( "b. Write an equation for the motion of the motorboat upstream.
\n" ); document.write( "c. Find the speed of the current. \r
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Algebra.Com's Answer #275006 by stanbon(75887)\"\" \"About 
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A motorboat can go 16 miles downstream on a river in 20 minutes. It takes 30 minutes for this boat to go back upstream the same 16 miles.
\n" ); document.write( "Let x = the speed of the boat.
\n" ); document.write( "Let y = the speed of the current. \r
\n" ); document.write( "\n" ); document.write( "a. Write an equation for the motion of the motorboat downstream.
\n" ); document.write( "x+y = 16/(1/5) = 80 mph
\n" ); document.write( "b. Write an equation for the motion of the motorboat upstream.
\n" ); document.write( "x-y = 16/(1/2) = 32 mph
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\n" ); document.write( "c. Find the speed of the current.
\n" ); document.write( "Subtract and solve for \"y\":
\n" ); document.write( "2y = 80-32
\n" ); document.write( "2y = 48 mph
\n" ); document.write( "y = 24 mph (rate of the current)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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