document.write( "Question 526730: A man rows a boat 825 feet upstream against a constant current in 15 minutes. He then rows 390 feet downstream (with the same current) in 6 minutes. \r
\n" ); document.write( "\n" ); document.write( "(a) Find the speed of the current. (Round your answer to the nearest whole number.)
\n" ); document.write( "_______ ft/min\r
\n" ); document.write( "\n" ); document.write( "(b) Find the equivalent rate at which boat can row in still water. (Round your answer to the nearest whole number.)
\n" ); document.write( "______ ft/min \n" ); document.write( "
Algebra.Com's Answer #348740 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
A man rows a boat 825 feet upstream against a constant current in 15 minutes.
\n" ); document.write( " He then rows 390 feet downstream (with the same current) in 6 minutes.
\n" ); document.write( ":
\n" ); document.write( "Find his effective rate rowing upstream\" 825/15 = 55 ft/min
\n" ); document.write( "Find his effective rate rowing downstream 390/6 = 65 ft/min
\n" ); document.write( ":
\n" ); document.write( "Let r = the rate in still water
\n" ); document.write( "Let c = the rate of the current
\n" ); document.write( ":
\n" ); document.write( "Write an equation for each scenario:
\n" ); document.write( "r - c = 55
\n" ); document.write( "r + c = 65
\n" ); document.write( "------------adding eliminates c, find r
\n" ); document.write( "2r = 120
\n" ); document.write( "r = 120/2
\n" ); document.write( "r = 60 ft/min in still water
\n" ); document.write( ":
\n" ); document.write( "Find the rate of the current
\n" ); document.write( "60 + c = 65
\n" ); document.write( "c = 65 - 60
\n" ); document.write( "c = 5 ft/min is the current \n" ); document.write( "
\n" );