document.write( "Question 60758: The speed of a stream in 5 mph. If a boat travels 82 miles downstream in the same time that it takes to travel 41 miles upstream, what is the speed of the boat in still water? \n" ); document.write( "

Algebra.Com's Answer #41732 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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The speed of a stream in 5 mph. If a boat travels 82 miles downstream in the same time that it takes to travel 41 miles upstream, what is the speed of the boat in still water?
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\n" ); document.write( "SInce the times are given as equal we can make a time equation:
\n" ); document.write( "Let s = speed in still water:
\n" ); document.write( "(s+5) = speed down stream
\n" ); document.write( "(s-5) = speed up stream
\n" ); document.write( "time = dist/speed
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\n" ); document.write( " $\"82%2F%28s%2B5%29\"$ = $\"41%2F%28s-5%29\"$
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\n" ); document.write( "Cross mult and you have:
\n" ); document.write( "82(s-5) = 41(s+5)
\n" ); document.write( "82s - 410 = 41s + 205
\n" ); document.write( "82s - 41s = 205 + 410
\n" ); document.write( "41s = 615
\n" ); document.write( "s = 15 mph
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\n" ); document.write( "Check solution by finding the time: 82/20 = 41/10 = 4.1 hrs \n" ); document.write( "

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