document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=509037>Question 509037</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The speed of a boat in still water is 4 miles per hour. If the boat travels 5 miles downstream in the same amount of time it takes to travel 2.5 miles upstream, 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 #341238 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=341238\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Boat speed	=	4	mph										<BR>\n" );
document.write( "current speed 	=	x	mph										<BR>\n" );
document.write( "wind speed													<BR>\n" );
document.write( "speed against	current	4	-	x									<BR>\n" );
document.write( "speed with	current	4	+	x									<BR>\n" );
document.write( "													<BR>\n" );
document.write( "Distance against	current	2.5	m 										<BR>\n" );
document.write( "Distance with 	current	5	m 										<BR>\n" );
document.write( "													<BR>\n" );
document.write( "t=d/r	time against = time with												<BR>\n" );
document.write( "2.5/(4-x)=5/(4+x)<BR>\n" );
document.write( "2.5(4+x)=5(4-x)			<BR>\n" );
document.write( "10+2.5x	=20-5x 					<BR>\n" );
document.write( "5x+2.5x	=10								<BR>\n" );
document.write( "7.5x=10										<BR>\n" );
document.write( "/	7.5												<BR>\n" );
document.write( "x =1.33	mph	current speed 									<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );