document.write( "Question 363370: A boat can travel 120 miles upstream against the current in the same amount of time it can travel 180 miles downstream with the current. If the boat's average speed in still water is 20 miles per hour, find the speed of the current. \n" ); document.write( "
Algebra.Com's Answer #259091 by mananth(16949)\"\" \"About 
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A boat can travel 120 miles upstream against the current in the same amount of time it can travel 180 miles downstream with the current. If the boat's average speed in still water is 20 miles per hour, find the speed of the current.
\n" ); document.write( "..
\n" ); document.write( "let current speed be x
\n" ); document.write( "..
\n" ); document.write( "upstream speed =20-x
\n" ); document.write( "distance = 120 miles
\n" ); document.write( "time = 120/(20-x)
\n" ); document.write( "..
\n" ); document.write( "down stream speed = x+20
\n" ); document.write( "distance = 180 miles
\n" ); document.write( "time = 180/(x+20)
\n" ); document.write( "...
\n" ); document.write( "times are equal
\n" ); document.write( "120/(20-x)=180/(x+20)
\n" ); document.write( "120(x+20)=180(20-x)
\n" ); document.write( "120x+2400=3600-180x
\n" ); document.write( "120x+180x=3600-2400
\n" ); document.write( "300x=1200
\n" ); document.write( "x= 4 mph the speed of current.\r
\n" ); document.write( "\n" ); document.write( "...
\n" ); document.write( "m.ananth@hotmail.ca \n" ); document.write( "
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