document.write( "Question 90989: A mississippi riverboat can travel 30km downstream in 3 hours and make the return trip in 5 hours. Find the speed of the boat in still water. \n" ); document.write( "
Algebra.Com's Answer #66047 by stanbon(75887)\"\" \"About 
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A mississippi riverboat can travel 30km downstream in 3 hours and make the return trip in 5 hours. Find the speed of the boat in still water.
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\n" ); document.write( "Downstream DATA:
\n" ); document.write( "distance = 30 km ; time = 3 hrs ; rate = d/t = 10kph
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\n" ); document.write( "Upstream DATA:
\n" ); document.write( "distance = 30 km ; time = 5 hrs ; rate = d/t = 6 kph
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\n" ); document.write( "let b be the speed of the riverboat in still water
\n" ); document.write( "let c be the speed of the current
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\n" ); document.write( "EQUATION:
\n" ); document.write( "b+c=10 kph
\n" ); document.write( "b-c=6 kph
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\n" ); document.write( "Add to get:
\n" ); document.write( "2b = 16 kph
\n" ); document.write( "b = 8 kph (this is the speed of the riverboat in still water)
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\n" ); document.write( "Substitute to solve for current speed:
\n" ); document.write( "8+c=10
\n" ); document.write( "c=2 kph (this is the speed of the current)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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