document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=120264>Question 120264</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question:<BR>\n" );
document.write( "James paddled his boat upstream for one mile. He continued for <BR>\n" );
document.write( "another 15 minutes, then turned around and paddled downstream, <BR>\n" );
document.write( "arriving at his starting point in exactly 1 hour.How fast is the <BR>\n" );
document.write( "current of the stream?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #88495 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=88495\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> James paddled his boat upstream for one mile. He continued for<BR>\n" );
document.write( "another 15 minutes, then turned around and paddled downstream,<BR>\n" );
document.write( "arriving at his starting point in exactly 1 hour.How fast is the<BR>\n" );
document.write( "current of the stream?<BR>\n" );
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document.write( "I am not real happy with what I came up with, but here it is:<BR>\n" );
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document.write( "Going over what you had:<BR>\n" );
document.write( "Solution:This is what i did,I defined 2 variables<BR>\n" );
document.write( "B = speed of boat in still water, in miles per hour<BR>\n" );
document.write( "C = speed of current, in miles per hour\r<BR>\n" );
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document.write( "Distance Rate Time<BR>\n" );
document.write( "Upstream 1 mile + 1/4hr(B-C) B-C 1/4hr<<<<<BR>\n" );
document.write( "The problem here is we don't know total time of the upstream trip at this point<BR>\n" );
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document.write( "The distance both ways can be written as (1+.25(B-C))<BR>\n" );
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document.write( "On the return trip, this distance was covered in 1 hr so we can also say:<BR>\n" );
document.write( " (1+.25(B-C)) mph,  the speed can also be written (B+C)mph<BR>\n" );
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document.write( "A Speed equation: <BR>\n" );
document.write( "(1+.25(B-C)) = (B+C)<BR>\n" );
document.write( "1 + .25B - .25C = B + C<BR>\n" );
document.write( "1 +.25B - B - .25C - C = 0<BR>\n" );
document.write( "-.75B - 1.25C = -1<BR>\n" );
document.write( "or mult by -1<BR>\n" );
document.write( ".75B + 1.25C = +1<BR>\n" );
document.write( "Get rid of the decimals, multiply by 4<BR>\n" );
document.write( "3B + 5C = 4<BR>\n" );
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document.write( "But we have only 1 equation and two unknowns. I have been unable to generate<BR>\n" );
document.write( "another equation from the information given.<BR>\n" );
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document.write( "Taking the above equation and graphing it, where y is the speed in still water,<BR>\n" );
document.write( " and x is the speed of the current:<BR>\n" );
document.write( "3y + 5x = 4<BR>\n" );
document.write( "3y = -5x + 4<BR>\n" );
document.write( "y = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-5%2F3 ALIGN=MIDDLE  ALT=\"-5%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >x + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F3 ALIGN=MIDDLE  ALT=\"4%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >; plotting this we have:<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+200%2C+-1%2C+2%2C+-2%2C+3%2C+-%285%2F3%29x+%2B+%284%2F3%29%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+200%2C+-1%2C+2%2C+-2%2C+3%2C+-%285%2F3%29x+%2B+%284%2F3%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You can see the positive values are very limited,<BR>\n" );
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document.write( "If you had a still water speed of 1 mph, the current would be .2 mph. <BR>\n" );
document.write( "this would work in our problem, B=1; C=.2<BR>\n" );
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document.write( "Distance 1 + .25(1-.2) = 1 + .25(.8) = 1.2 mi is the distance<BR>\n" );
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document.write( "The downstream speed 1 + .2 = 1.2 mph and of course to cover 1.2 mi would be 1 hr<BR>\n" );
document.write( "This would be the only still water speed that is an integer<BR>\n" );
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document.write( "As I said I am not real happy with it.  </SPAN>\n" );
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