document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=701751>Question 701751</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For the following problem, clearly define the variable(s) and write an equation that could be used to solve the problem. What are the units of the answer.\r<BR>\n" );
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document.write( "Two tugboats that have the same speed in still water travel in opposite directions in a river with a constant current of 5 miles per hour. The tugboats departed at the same time from a refueling station; and after a period of time, one has traveled 30 miles downstream and the other has traveled 6 miles upstream. Determine the rate of each boat 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 #432575 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=432575\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The tugboat going upstream is slowed by 5 mph, so speed is r-5 mph; letting r equal speed in still water.  The tugboat going downstream is going WITH the current and its speed is increased by 5 mph, so speed is r+5 mph.<BR>\n" );
document.write( "Let t = time in hours.\r<BR>\n" );
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document.write( "One can make a table using this format:\r<BR>\n" );
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document.write( "Which Direction: Speed(miles per hour), Time(hours), Distance(miles)<BR>\n" );
document.write( "Upstream:     r-5, t, 30<BR>\n" );
document.write( "Downstream:   r+5, t, 6\r<BR>\n" );
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document.write( "Find two expressions for the travel time, which are equal for the both boats.<BR>\n" );
document.write( "Upstream,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=30%2F%28r-5%29 ALIGN=MIDDLE  ALT=\"t=30%2F%28r-5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Downstream,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=6%2F%28r%2B5%29 ALIGN=MIDDLE  ALT=\"t=6%2F%28r%2B5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The formulas for t are equal, so  \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2F%28r-5%29=t=6%2F%28r%2B5%29 ALIGN=MIDDLE  ALT=\"30%2F%28r-5%29=t=6%2F%28r%2B5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Most of the effort is analyzing the situation and setting up the relationship equation.  Solve for r. </SPAN>\n" );
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