document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1072429>Question 1072429</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2. A boat, which moves at 11 mph in water without a current, goes 56 miles upstream and 56 back again in 11 hours. Find the speed of the current to the nearest tenth.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #687349 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=687349\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A boat, which moves at 11 mph in water without a current, goes 56 miles upstream and 56 back again in 11 hours.<BR>\n" );
document.write( " Find the speed of the current to the nearest tenth.<BR>\n" );
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document.write( "let c = the rate of the current<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(11-c) = effective speed upstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(11+c) = effective speed downstream<BR>\n" );
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document.write( "Write a time equation. time = dis/speed<BR>\n" );
document.write( "up time + down time = 11 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=56%2F%28%2811-c%29%29 ALIGN=MIDDLE  ALT=\"56%2F%28%2811-c%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=56%2F%28%2811%2Bc%29%29 ALIGN=MIDDLE  ALT=\"56%2F%28%2811%2Bc%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 11 <BR>\n" );
document.write( "multiply equation by (11-c)(11+c), cancel the denominators<BR>\n" );
document.write( "56(11+c) + 56(11-c) = 11(11+c)(11-c)<BR>\n" );
document.write( "distribute and FOIL<BR>\n" );
document.write( "616 + 56c + 616 - 56c = 11(121 - c^2)<BR>\n" );
document.write( "1232 = 1331 - 11c^2<BR>\n" );
document.write( "11c^2 = 1331 - 1232<BR>\n" );
document.write( "11c^2 = 99<BR>\n" );
document.write( "c^2 = 99/11<BR>\n" );
document.write( "c^2 = 9<BR>\n" );
document.write( "c = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%289%29 ALIGN=MIDDLE  ALT=\"sqrt%289%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c = 3 mph is the rate of the current<BR>\n" );
document.write( ":<BR>\n" );
document.write( ";<BR>\n" );
document.write( "Check this by finding the actual time each way<BR>\n" );
document.write( "56/8 = 7 hrs<BR>\n" );
document.write( "56/14 = 4 hrs<BR>\n" );
document.write( "=============<BR>\n" );
document.write( "tot time 11 hrs </SPAN>\n" );
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