document.write( "Question 180882This question is from textbook ELEMENTARY AND INTERMEDIATE ALGEBRA
\n" ); document.write( ": I am totally confused on how to begin this problem, if someone could help it would be greatly appreciated.
\n" ); document.write( "Junior's boat will go 15 miles per hour in still water. If he can go 12 miles downstream in the same amount of time as it takes to go 9 miles upstream, then what is the speed of the current? \n" ); document.write( "
Algebra.Com's Answer #135613 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
You 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
\n" ); document.write( ".
\n" ); document.write( "Let x = speed of the current
\n" ); document.write( "then
\n" ); document.write( "12/(15+x) = 9/(15-x)
\n" ); document.write( "12(15-x) = 9(15+x)
\n" ); document.write( "4(15-x) = 3(15+x)
\n" ); document.write( "60-4x = 45+3x
\n" ); document.write( "60 = 45+7x
\n" ); document.write( "15 = 7x
\n" ); document.write( "15/7 = x
\n" ); document.write( "or
\n" ); document.write( "2.1429 mph = x
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