document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1007208>Question 1007208</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A man rows a boat 910 feet upstream against a constant current in 14 minutes. He then rows 525 feet downstream (with the same current) in 7 minutes. Find the speed of the current and the equivalent rate at which he can row in still water. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #623189 by </B><A HREF=/tutors/aboutme.mpl?userid=addingup><B>addingup(3677)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=addingup><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=addingup><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=623189\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let speed of rowing be x feet per minute AND speed of current be y feet per minute.<BR>\n" );
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document.write( "Let's remember the formula we need to use, it's the one for distance modified:<BR>\n" );
document.write( "Distance= Speed*time Since we want the speed of the current, divide both sides by time:<BR>\n" );
document.write( "D/t= S*t/t On the right, t multiplying and t dividing cancel each other and we get:<BR>\n" );
document.write( "D/t= S This is the formula we will use, which we derived from D= St<BR>\n" );
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document.write( "UPSTREAM<BR>\n" );
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document.write( "x - y ft/minute= Speed upstream<BR>\n" );
document.write( "x - y = 910/14<BR>\n" );
document.write( "x - y = 65 Add y on both sides:<BR>\n" );
document.write( "x = 65+y<BR>\n" );
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document.write( "DOWNSTREAM<BR>\n" );
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document.write( "x + y = 525/7<BR>\n" );
document.write( "x + y = 75 Now substitute for x, since we just said that x= 65+y:<BR>\n" );
document.write( "65+y+y= 75<BR>\n" );
document.write( "2y= 75 - 65<BR>\n" );
document.write( "2y= 10 divide both sides by 2:<BR>\n" );
document.write( "y= 5 The speed of the current is 5 feet per minute<BR>\n" );
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document.write( "(A) + (B)= 65 + 75= 140\r<BR>\n" );
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document.write( "2x = 100\r<BR>\n" );
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document.write( "x = 50 ' / minute ANSWER\r<BR>\n" );
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document.write( "y = 5' / minute ANSWER<BR>\n" );
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