document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=290439>Question 290439</A>: <I><SPAN STYLE=\"word-break: break-all;\">  <BR>\n" );
document.write( "This is driving me crazy. I finally solved my problem, but I can’t figure out why my ‘tweaking’ made a difference. The problem reads:<BR>\n" );
document.write( "“A bus traveled at an average rate of 50 mph and then reduced its average rate to 40 mph for the rest of the trip. If the 220-mile trip took 5 hours, determine how long the bus traveled at each rate.” \r<BR>\n" );
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document.write( "So I set up my little table: (apparently there are spacing issues and I can't lay the table out here.)  In short I used 'x' for the 'time' on the 50 mph leg of the trip, and '5-x' for the 'time' on the 40 mph leg of the trip.<BR>\n" );
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document.write( "And then I did the math: \r<BR>\n" );
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document.write( "50x + 40(5-x) = 220<BR>\n" );
document.write( "50x + 200 -40x = 220<BR>\n" );
document.write( "10x = 20<BR>\n" );
document.write( "X = 10 \r<BR>\n" );
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document.write( "I knew that couldn’t be right as the answer made no sense, but I couldn’t (and still can’t) figure out what I did wrong. I finally switched things around in my table changing the time of the 40mph leg to 'x' and the 50mph leg to '5-x'.  It would be easier if I could show you my table...hopefull you understand what I'm trying to say. \r<BR>\n" );
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document.write( " All I did was switch the factors around in the “time” row and when I did the math that way the answer came out correctly. Why did that make a difference? I would have thought it would have worked either way. Or maybe I made my mistake the first time elsewhere? (I sure hope I copied everything correctly). I have a similar problem (except it involves interest rates and bank accounts) where the same thing happened. I thought as long as I made one account \"x\" and the other \"Blah-x\" it didn't matter which I used for which. Maybe I've just made simple math errors when I did them the first time? \r<BR>\n" );
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document.write( "Thanks a million...you guys rock! <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #210163 by </B><A HREF=/tutors/aboutme.mpl?userid=kensson><B>kensson(21)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=kensson><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=kensson><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=210163\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I think you're going to kick yourself. \r<BR>\n" );
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document.write( "10x=20<BR>\n" );
document.write( "x = 2. </SPAN>\n" );
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