document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=402625>Question 402625</A>: <I><SPAN STYLE=\"word-break: break-all;\"> When two cars race around a circular mile track starting from the same place at the same instance, they pass each other every 18 seconds when traveling in opposite directions and every 90 seconds when traveling in the same direction. Find their speeds in miles per hour  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #284768 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=284768\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x = rate of one car<BR>\n" );
document.write( "y = rate of another car.\r<BR>\n" );
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document.write( "Then 18x + 18y = 1, and <BR>\n" );
document.write( "90x - 90y = 1\r<BR>\n" );
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document.write( "Multiply the top equation by 5 and add to the bottom equation:\r<BR>\n" );
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document.write( "180x = 6, or x = 1/30 mile per second, or 2 miles per hour.\r<BR>\n" );
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document.write( "==> y = 1/45 mile per second, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%261%2F3 ALIGN=MIDDLE  ALT=\"1%261%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > miles per hour. </SPAN>\n" );
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