document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=783860>Question 783860</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat travels145 mi  in 5 hours going upstream. It travels 215  going downstream in the same amount of time. What is the rate of the boat in still water and what is 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 #476946 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</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=476946\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let r = speed of boat in still water<BR>\n" );
document.write( "let c = speed of the current\r<BR>\n" );
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document.write( "Direction___________speed__________time____________distance<BR>\n" );
document.write( "UP__________________r-c____________5_______________145<BR>\n" );
document.write( "DOWN________________r+c____________5_______________215\r<BR>\n" );
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document.write( "Most basically, r*t=d so we form two equations from the data table.\r<BR>\n" );
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document.write( "(r-c)5=145 and (r+c)5=215<BR>\n" );
document.write( "5r-5c=145 and 5r+5c=215\r<BR>\n" );
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document.write( "Solve the system:<BR>\n" );
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document.write( "5r-5c=145<BR>\n" );
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document.write( "5r+5c=215<BR>\n" );
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document.write( "Best way to begin solving the system is sum the lefthand members, sum the righthand members, and equate these.  You would then immediately find the value for r.  Continue any reasonable way to solve for and find c. </SPAN>\n" );
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