document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=918875>Question 918875</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two campers left the camp at 8:00 AM to paddle their canoe 10 Km upstream to a fishing cove.  They finished for 3.5 hours then paddled back to the campsite and arrived 6:00 PM.  If the rate of the current was 3 km/hr. How fast could the camper paddle in still water? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #557286 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=557286\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Two campers left the camp at 8:00 AM to paddle their canoe 10 Km upstream to a fishing cove.  They finished for 3.5 hours then paddled back to the campsite and arrived 6:00 PM.  If the rate of the current was 3 km/hr. How fast could the camper paddle in still water?\r<BR>\n" );
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document.write( "let the rate of boat in still water be x\r<BR>\n" );
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document.write( "upstream time = 10/(x-3)\r<BR>\n" );
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document.write( "Time spent there = 3.5 hours\r<BR>\n" );
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document.write( "down stream time = 10/(x+3)\r<BR>\n" );
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document.write( "They left at 8.00 and reached at 6.00 pm\r<BR>\n" );
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document.write( "=10 hours\r<BR>\n" );
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document.write( "10/(x-3)+3.5+10/(x+3) = 10\r<BR>\n" );
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document.write( "10/(x-3)+10/(x+3) = 10-3.5\r<BR>\n" );
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document.write( "10/(x-3)+10/(x+3) = 6.5\r<BR>\n" );
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document.write( "take the LCM \r<BR>\n" );
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document.write( "10(x+3)+10(x-3)= 6.5(x+3)(x-3)\r<BR>\n" );
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document.write( "10x+30+10x-30=6.5(x^2-9)\r<BR>\n" );
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document.write( "20x=6.5x^2-58.5\r<BR>\n" );
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document.write( "6.5x^2-20x-58.5=0\r<BR>\n" );
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document.write( "Find the roots of the equation by quadratic formula							<BR>\n" );
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document.write( "a=	6.5	,	b=	-20	,	c=	-58.5<BR>\n" );
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document.write( "b^2-4ac=	400	+	1521				<BR>\n" );
document.write( "b^2-4ac=	1921						<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%09sqrt%28%091921%09%29=%0943.83%09 ALIGN=MIDDLE  ALT=\"%09sqrt%28%091921%09%29=%0943.83%09\"   DISABLED_style= \"max-width:90%; height:auto;\" >		<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >							<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >							<BR>\n" );
document.write( "x1=(	20	+	43.83	)/	13		<BR>\n" );
document.write( "x1=	4.91						<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >							<BR>\n" );
document.write( "x2=(	20	-43.83	) /	13			<BR>\n" );
document.write( "x2=	-1.83						<BR>\n" );
document.write( "Ignore negative value							<BR>\n" );
document.write( "boat   	speed	4.910	km/h				\r<BR>\n" );
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document.write( " </SPAN>\n" );
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