document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=456708>Question 456708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boy swims downstream 0.9 miles in the same amount of time that he can swim 0.6 miles upstream. If the rate of the current is 1.5 mph, how fast can he swim in still water?\r<BR>\n" );
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document.write( "help!!! :( </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #313500 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=313500\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A boy swims downstream 0.9 miles in the same amount of time that he can swim 0.6 miles upstream. <BR>\n" );
document.write( "If the rate of the current is 1.5 mph, how fast can he swim in still water?<BR>\n" );
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document.write( "Let s = swim speed in still water<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+1.5) = effective speed downstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(s-1.5) = effective speed upstream<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a time equation: time = dist/speed<BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.9%2F%28s%2B1.5%29 ALIGN=MIDDLE  ALT=\".9%2F%28s%2B1.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.6%2F%28s-1.5%29 ALIGN=MIDDLE  ALT=\".6%2F%28s-1.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Cross multiply and solve for s <BR>\n" );
document.write( ".9(s-1.5) = .6(s+1.5)<BR>\n" );
document.write( ".9s - 1.35 = .6s + .9<BR>\n" );
document.write( ".9s - .6s = .9 + 1.35<BR>\n" );
document.write( ".3s = 2.25<BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2.25%2F.3 ALIGN=MIDDLE  ALT=\"2.25%2F.3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 7.5 mph in still water<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Check solution by finding the times, they should be equal<BR>\n" );
document.write( ".9/9 = .1<BR>\n" );
document.write( ".6/6 = .1<BR>\n" );
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