document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=116562>Question 116562</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A Car travels downhill at 72 mph, on the level at 63 mph, and uphill at 56 mph. The trip from point A to point B takes 4 hours, and the return trip takes 4 hours, 40 minutes. What's the distance between points A & B? Please give me the correct formulas/steps to work this problem out.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #86317 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=86317\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A Car travels downhill at 72 mph, on the level at 63 mph, and uphill at 56 mph. The trip from point A to point B takes 4 hours, and the return trip takes 4 hours, 40 minutes. What's the distance between points A & B?<BR>\n" );
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document.write( "Let distance on level ground be \"x\".<BR>\n" );
document.write( "Let distance uphill be \"y\".<BR>\n" );
document.write( "Let distance downhill be \"z\".<BR>\n" );
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document.write( "Time = distance/rate<BR>\n" );
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document.write( "Note: uphill in one direction is downhill in the other; and vice versa.<BR>\n" );
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document.write( "EQUATIONS:<BR>\n" );
document.write( "level time + uphill time + downhill time = total time<BR>\n" );
document.write( "x/63 + y/56 + z/72 = 4 hrs<BR>\n" );
document.write( "x/63 + y/72 + z/56 = 4 2/3 hrs<BR>\n" );
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document.write( "Subtract to get:<BR>\n" );
document.write( "y(1/72 - 1/56) + z(1/56 -1/72) = 2/3<BR>\n" );
document.write( "y(-16/(72*56)) + z(16/(72*56)) = 2/3<BR>\n" );
document.write( "-16y + 16z = (2/3)72*56<BR>\n" );
document.write( "-16y + 16z = 48*56<BR>\n" );
document.write( "-y+z = 3*56<BR>\n" );
document.write( "-y+z = 168<BR>\n" );
document.write( "z = 168+y<BR>\n" );
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document.write( "Question:<BR>\n" );
document.write( "Do you have any more information that might help to resolve<BR>\n" );
document.write( "the value of y or of z?<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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