document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=304186>Question 304186</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Juniors boat will go 15 miles per hour in still water.  If he can go 12 miles downstream in the same amount of time as it takes to go 9 miles upstream, then what is the speed of the current.  \r<BR>\n" );
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document.write( "Word problems are definitely my weakness, they just don't make sense in my head.  I have a hard time figuring out which formula I need and what I need to do. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #217898 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=217898\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Juniors boat will go 15 miles per hour in still water.<BR>\n" );
document.write( " If he can go 12 miles downstream in the same amount of time as it takes to go 9 miles upstream, then what is the speed of the current.<BR>\n" );
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document.write( "See if this makes sense to you.<BR>\n" );
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document.write( "Let c = speed of the current<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(15+c) =  speed down stream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(15-c) = speed upstream<BR>\n" );
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document.write( "Write a time equation: Time = dist/speed<BR>\n" );
document.write( "Time up = time down<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2F%2815-c%29 ALIGN=MIDDLE  ALT=\"9%2F%2815-c%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2F%2815%2Bc%29 ALIGN=MIDDLE  ALT=\"12%2F%2815%2Bc%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "cross multiply<BR>\n" );
document.write( "9(15+c) = 12(15-c)<BR>\n" );
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document.write( "135 + 9c = 180 - 12c<BR>\n" );
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document.write( "9c + 12c = 180 - 135<BR>\n" );
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document.write( "21c = 45<BR>\n" );
document.write( "c = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=45%2F21 ALIGN=MIDDLE  ALT=\"45%2F21\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c = 2.143 mph is the current<BR>\n" );
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document.write( "Check solution,  by finding the times (they should be equal)<BR>\n" );
document.write( "9/12.857 = .7 hrs (subtracted the speed of the current from 15)<BR>\n" );
document.write( "12/17.143= .7 hrs (added the speed of the current to 15)<BR>\n" );
document.write( ":\r<BR>\n" );
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document.write( "How about this, did I explain this so you can see it?<BR>\n" );
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