document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=939391>Question 939391</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A barge travels along a river between Metro City and Smithport which are 50 miles away from each other. The speed of the current is 1.7 miles per hour. If the barge can make the downstream trip in 6.5 hours less than it can travel the upstream trip, then what is the barge's speed in still water? \r<BR>\n" );
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document.write( "My professor said the answer is 5.4 mph, but no matter what I try, I can't seem to come up with that answer. Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #572391 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=572391\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A barge travels along a river between Metro City and Smithport which are 50 miles away from each other. The speed of the current is 1.7 miles per hour. If the barge can make the downstream trip in 6.5 hours less than it can travel the upstream trip, then what is the barge's speed in still water? <BR>\n" );
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document.write( "let x=speed of barge in still water<BR>\n" );
document.write( "x+1.7=speed of barge downstream<BR>\n" );
document.write( "x-1.7=speed of barge upstream<BR>\n" );
document.write( "travel time=distance/speed<BR>\n" );
document.write( "..<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=50%2F%28x-1.7%29-50%2F%28x%2B1.7%29=6.5 ALIGN=MIDDLE  ALT=\"50%2F%28x-1.7%29-50%2F%28x%2B1.7%29=6.5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "lcd:(x-1.7)(x+1.7)<BR>\n" );
document.write( "50(x+1.7)-50(x-1.7)=6.5(x-1.7)(x+1.7)<BR>\n" );
document.write( "50x+85-50x+85=6.5(x^2-1.7^2)=6.5(x^2-2.89)=6.5x^2-18.785<BR>\n" );
document.write( "170=6.5x^2-18.785<BR>\n" );
document.write( "6.5x^2=188.785<BR>\n" );
document.write( "x^2=188.785/6.5=29.04<BR>\n" );
document.write( "x=&#8730;29.04=5.4 (rounded)<BR>\n" );
document.write( "speed of barge in still water&#8776;5.4 mph </SPAN>\n" );
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