document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1065811>Question 1065811</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat takes 5 hours to travel 200km going upstream. The return trip takes 4 hours going downstream. <BR>\n" );
document.write( "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 #680976 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52811)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=680976\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "A motorboat takes 5 hours to travel 200km going upstream. The return trip takes 4 hours going downstream. <BR>\n" );
document.write( "What is the rate of the boat in still water and what is the rate of the current?<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=200%2F5 ALIGN=MIDDLE  ALT=\"200%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > = u - v   (1)   ( the speed upstream)\r\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=200%2F4 ALIGN=MIDDLE  ALT=\"200%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = u + v   (2)   ( the speeddownstream)\r\n" );
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document.write( "Or, which is the same,\r\n" );
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document.write( "u - v = 40,    (1')\r\n" );
document.write( "u + v = 50.    (2')\r\n" );
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document.write( "Add equations (1') and (2') (both sides). You will get\r\n" );
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document.write( "2u = 50 + 40  ---->  2u = 90  ---->  u = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=90%2F2 ALIGN=MIDDLE  ALT=\"90%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 45.\r\n" );
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document.write( "The speed of the boat is 45 mph in still water.\r\n" );
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document.write( "The current speed is 5 mph.\r\n" );
document.write( "</PRE>\r<BR>\n" );
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document.write( "Solved.\r<BR>\n" );
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document.write( "It is a typical and standard Upstream and Downstream round trip word problem.\r<BR>\n" );
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document.write( "You can find many similar fully solved problems on upstream and downstream round trips with detailed solutions in lessons \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/word/travel/Wind-and-Current-problems.lesson>Wind and Current problems</A> \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/word/travel/More-problems-on-upstream-and-downstream-round-trips.lesson>More problems on upstream and downstream round trips</A> \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/word/travel/Selected-problems-from-the-archive-on-a-boat-floating-Upstream-and-Downstream.lesson>Selected problems from the archive on the boat floating Upstream and Downstream</A> \r<BR>\n" );
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document.write( "in this site.\r<BR>\n" );
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document.write( "Read them attentively and learn how to solve this type of problems once and for all.\r<BR>\n" );
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document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.\r<BR>\n" );
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document.write( "The referred lessons are the part of this textbook under the section \"<U>Word problems</U>\", the topic \"<U>Travel and Distance problems</U>\".\r<BR>\n" );
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document.write( " </SPAN>\n" );
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