document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=28317>Question 28317</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The speed of a stream is 4 mph. If a boat travels 52 miles downstream in the same time that it takes to travel 26 miles upstream, what is the speed on the 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 #15391 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=15391\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The thing that stays the same for both trips is elapsed time\r<BR>\n" );
document.write( "\n" );
document.write( "Solve the rate formula for t<BR>\n" );
document.write( "time = distance / rate<BR>\n" );
document.write( "The times are equal, so<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=distance%5B1%5D+%2F+rate%5B1%5D+=+distance%5B2%5D+%2F+rate%5B2%5D ALIGN=MIDDLE  ALT=\"distance%5B1%5D+%2F+rate%5B1%5D+=+distance%5B2%5D+%2F+rate%5B2%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The rate for downstream is the rate in still water + rate of the current<BR>\n" );
document.write( "The rate for upstream is the rate in still water - rate of the current<BR>\n" );
document.write( "Fill in the values<BR>\n" );
document.write( "Call the rate in still water r<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=52+%2F+%28r+%2B+4%29+=+26+%2F+%28r+-+4%29 ALIGN=MIDDLE  ALT=\"52+%2F+%28r+%2B+4%29+=+26+%2F+%28r+-+4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Cross multiply<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=26%2Ar+%2B+104+=+52%2Ar+-+208 ALIGN=MIDDLE  ALT=\"26%2Ar+%2B+104+=+52%2Ar+-+208\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=26%2Ar+=+312 ALIGN=MIDDLE  ALT=\"26%2Ar+=+312\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+12 ALIGN=MIDDLE  ALT=\"r+=+12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So, the speed in still water is 12 mph<BR>\n" );
document.write( "Check by plugging into equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=52+%2F+%2812+%2B+4%29+=+26+%2F+%2812+-+4%29 ALIGN=MIDDLE  ALT=\"52+%2F+%2812+%2B+4%29+=+26+%2F+%2812+-+4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=52+%2F+16+=+26+%2F+8 ALIGN=MIDDLE  ALT=\"52+%2F+16+=+26+%2F+8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13%2F4+=+13%2F4 ALIGN=MIDDLE  ALT=\"13%2F4+=+13%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Checks </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );