document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=316542>Question 316542</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a motor boat maintained  speed of 27 miles per hour relative to the water going 20 miles upstream and returning. The total time of the trip was 1.5 hours. What is the speed of the current? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #226516 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=226516\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a motor boat maintained speed of 27 miles per hour relative to the water going 20 miles upstream and returning.<BR>\n" );
document.write( " The total time of the trip was 1.5 hours. What is the speed of the current?<BR>\n" );
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document.write( "Let c = speed of the current<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(27-c) = effective speed upstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(27+c) = effective speed downstream<BR>\n" );
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document.write( "Write a time equation; time = dist/speed<BR>\n" );
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document.write( "Time up + time down = 1.5 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2F%2827-c%29 ALIGN=MIDDLE  ALT=\"20%2F%2827-c%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2F%2827%2Bc%29 ALIGN=MIDDLE  ALT=\"20%2F%2827%2Bc%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1.5<BR>\n" );
document.write( "Multiply equation by (27-c)(27+c), results<BR>\n" );
document.write( "20(27+c) + 20(27-c) = 1.5(27-c)(27+c)<BR>\n" );
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document.write( "540 + 20c + 540 - 20c = 1.5(729-c^2)<BR>\n" );
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document.write( "1080 = 1093.5 - 1.5c^2<BR>\n" );
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document.write( "1.5c^2 = 1093.5 - 1080<BR>\n" );
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document.write( "1.5c^2 = 13.5<BR>\n" );
document.write( "c^2 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13.5%2F1.5 ALIGN=MIDDLE  ALT=\"13.5%2F1.5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><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 speed of the current<BR>\n" );
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document.write( "See if that's true, find the time of each<BR>\n" );
document.write( "20/30 = .67<BR>\n" );
document.write( "20/24 = .83<BR>\n" );
document.write( "-------------<BR>\n" );
document.write( "totals:1.5 hrs </SPAN>\n" );
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