document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=761849>Question 761849</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A speed boat has a speed of 27 mph in still water. If it requires 1 1/8 hours for the boat to go 15 miles downstream and return, what is the speed of the current?\r<BR>\n" );
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document.write( "Here is how I set up the problem:<BR>\n" );
document.write( "c=the current speed t= the time for downstream<BR>\n" );
document.write( "27-c*(1 1/8 -t)=15<BR>\n" );
document.write( "27+c*(t)=15<BR>\n" );
document.write( "Do I have the problem set up right 1st of all?<BR>\n" );
document.write( "I rearrange the second equation and plug it into the first to get this:<BR>\n" );
document.write( "27-c(1 1/8-(15/(27+c)))=15 <BR>\n" );
document.write( "If this is right, how do I solve it?<BR>\n" );
document.write( "Thank you so much! Abby </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #463517 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=463517\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A speed boat has a speed of 27 mph in still water. If it requires 1 1/8 hours for the boat to go 15 miles downstream and return, what is the speed of the current?<BR>\n" );
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document.write( "upstream DATA:<BR>\n" );
document.write( "dist = 15 miles ; rate = 27-c mph ; time = 15/(27-c) hrs<BR>\n" );
document.write( "----<BR>\n" );
document.write( "downstream DATA:<BR>\n" );
document.write( "dist = 15 miles ; rate = 27+c mph ; time = 15/(27+c) hrs<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Equations;<BR>\n" );
document.write( " 15/(27-c) + 15/(27+c) = 9/8 hrs<BR>\n" );
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document.write( "Multiply thru by 8(27-c)(27+c) to get:<BR>\n" );
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document.write( "8*15(27+c) + 8*15(27-c) = 9(27^2-c)^2<BR>\n" );
document.write( "-------<BR>\n" );
document.write( "120*27 + 120*27 = 9(27^2-c^2)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "2(120*27) = 9(27^2-c^2)<BR>\n" );
document.write( "6*120 = 27^2-c^2<BR>\n" );
document.write( "c^2 = 9<BR>\n" );
document.write( "c = 3 mph (speed of the current)<BR>\n" );
document.write( "================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "=============== </SPAN>\n" );
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