document.write( "Question 514789: If Jim's boat goes 30 mph upstream and 50 mph downsteam. What is the speed of the current and the boat in still water? I HAVE NO IDEA HOW TO SET THIS UP!! thanks! \n" ); document.write( "
Algebra.Com's Answer #343688 by ankor@dixie-net.com(22740)\"\" \"About 
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If Jim's boat goes 30 mph upstream and 50 mph downsteam.
\n" ); document.write( " What is the speed of the current and the boat in still water?
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\n" ); document.write( "Let s = speed of the boat in still water
\n" ); document.write( "Let c = speed of the current
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\n" ); document.write( "s + c = 50; downstream
\n" ); document.write( "s - c = 30; upstream
\n" ); document.write( "-------------------------adding eliminates c find s
\n" ); document.write( "2s = 80
\n" ); document.write( "s = 80/2
\n" ); document.write( "s = 40 mph in still water
\n" ); document.write( ":
\n" ); document.write( "Find the current using the 1st equation
\n" ); document.write( "40 + c = 50
\n" ); document.write( "c = 50 - 40
\n" ); document.write( "c = 10 mph is current
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