document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=209211>Question 209211</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Julie and Eric row their boat (at a constant speed) 45 miles downstream for 5 hours, helped by the current. Rowing at the same rate, the trip back against the current takes 9 hours. Find the rate of the current. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #158156 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10551)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=158156\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Julie and Eric row their boat (at a constant speed) 45 miles downstream for 5 hours, helped by the current. Rowing at the same rate, the trip back against the current takes 9 hours. Find the rate of the current.\r<BR>\n" );
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document.write( "The speed that they travelled at, downstream, with the current = 9 mph (45/5) \r<BR>\n" );
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document.write( "The speed that they travelled at, upstream, against the current = 5 mph (45/9) \r<BR>\n" );
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document.write( "Let the rate of the current be C\r<BR>\n" );
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document.write( "Then we'll have: Downstream speed - current = Upstream speed + current, or,\r<BR>\n" );
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document.write( "9 - C = 5 + C\r<BR>\n" );
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document.write( "- 2C  =  - 4\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C+=+%28-4%29%2F-2+=+2 ALIGN=MIDDLE  ALT=\"C+=+%28-4%29%2F-2+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Therefore, the speed of the current is: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%282%29 ALIGN=MIDDLE  ALT=\"highlight_green%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > mph.<BR>\n" );
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