document.write( "Question 168443: The speed of a stream is 3 mph. A boat travels 5 miles upstream in the same time it takes to travel 11 miles downstream. What is the speed of the boat in still water? \n" ); document.write( "
Algebra.Com's Answer #124174 by nerdybill(7384)\"\" \"About 
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The speed of a stream is 3 mph. A boat travels 5 miles upstream in the same time it takes to travel 11 miles downstream. What is the speed of the boat in still water?
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\n" ); document.write( "You will need to apply the \"distance formula\":
\n" ); document.write( "d = rt
\n" ); document.write( "where
\n" ); document.write( "d is distance
\n" ); document.write( "r is rate or speed
\n" ); document.write( "t is time
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\n" ); document.write( "Since this problem is talking about \"time\" solve the equation for 't':
\n" ); document.write( "d =rt
\n" ); document.write( "d/r = t
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\n" ); document.write( "Let x = speed of boat in still water
\n" ); document.write( "5/(x-3) = 11/(x+3)
\n" ); document.write( "Multiplying both sides by (x+3)(x-3):
\n" ); document.write( "5(x+3) = 11(x-3)
\n" ); document.write( "5x+15 = 11x-33
\n" ); document.write( "15 = 6x-33
\n" ); document.write( "48 = 6x
\n" ); document.write( "8 mph = x (speed of boat in still water)\r
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