document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1074804>Question 1074804</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bill starts riding his bike towards town at a constant rate of 8 mph. Then, 30 minutes later, his wife starts driving on the same path at a constant average of 30 mph. How long will it take her to catch up to Bill?\r<BR>\n" );
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document.write( "This question is from a study packet, that also has the answer shown as\r<BR>\n" );
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document.write( "8(.5)/30-8 = approx. 18 hours = approx. 10.8 mins = approx 10 minutes 48 seconds.\r<BR>\n" );
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document.write( "When I solve the problem that way, I understand the answer. However, based on my understanding of DRT problems, that doesn't seem correct.  The way I solve this is using a table\r<BR>\n" );
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document.write( "Persons     R      T     D<BR>\n" );
document.write( "Bill        8mph   t     8(t)<BR>\n" );
document.write( "Wife        30mph  t-.5  30(t-.5)\r<BR>\n" );
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document.write( "8t=30(t-.5)<BR>\n" );
document.write( "=8t=30t-15<BR>\n" );
document.write( "=-22t=-15<BR>\n" );
document.write( "=-15/-22<BR>\n" );
document.write( "=.68 <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #689461 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=689461\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 8 mph*t h=8t miles<BR>\n" );
document.write( "30 mph (t-0.5)=30t-15 miles<BR>\n" );
document.write( "those are equal<BR>\n" );
document.write( "30t-15=8t<BR>\n" );
document.write( "22t=15<BR>\n" );
document.write( "t=15/22 hrs. or 0.682 hours<BR>\n" );
document.write( "He will travel 5.458 miles<BR>\n" );
document.write( "She will travel 30*(.182)=5.46 miles. That checks<BR>\n" );
document.write( ".682 hours is 40.92 minutes <BR>\n" );
document.write( "She will travel 10.92 minutes, which is 0.182 hours.  I get 10m 55.2 sec, but that is within rounding.<BR>\n" );
document.write( "Your 0.68 was the time the bicyclist rode.<BR>\n" );
document.write( "She drove a half hour less, so that has to be subtracted. </SPAN>\n" );
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