document.write( "Question 228633: In testing the rate at which a polluted stream flows, a boat that travels 5.5mi/hr in still water took 5 hrs to go down stream and 8 hrs to go upstream, between 2 points. what is the rate of flow of the stream \n" ); document.write( "
Algebra.Com's Answer #169750 by ankor@dixie-net.com(22740)\"\" \"About 
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a boat that travels 5.5mi/hr in still water took 5 hrs to go down stream
\n" ); document.write( "and 8 hrs to go upstream, between 2 points.
\n" ); document.write( "what is the rate of flow of the stream
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\n" ); document.write( "Let r = rate of flow of the stream
\n" ); document.write( "then
\n" ); document.write( "(5.5 + r) = boat speed down stream
\n" ); document.write( "and
\n" ); document.write( "(5.5 - r) = boat speed up stream
\n" ); document.write( ":
\n" ); document.write( "Write a distance equation, distance is the same for both trips
\n" ); document.write( "Dist = speed * time
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\n" ); document.write( "dist down = dist up
\n" ); document.write( "5(5.5 + r) = 8(5.5 - r)
\n" ); document.write( ":
\n" ); document.write( "27.5 + 5r = 44 - 8r
\n" ); document.write( ":
\n" ); document.write( "5r + 8r = 44 - 27.5
\n" ); document.write( ":
\n" ); document.write( "13r = 16.5
\n" ); document.write( "r = \"16.5%2F13\"
\n" ); document.write( "r ~ 1.27 mi/hr (flow of the stream)
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\n" ); document.write( "See if this is true; find the dist of each (should be equal)
\n" ); document.write( "5(5.5 + 1.27) = 33.8 mi
\n" ); document.write( "8(5.5 - 1.27) = 33.8 mi \n" ); document.write( "
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