document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=500895>Question 500895</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a car leaves san diego at 1 pm traveling at a constant rate of 40 mph toward LA. 30 mins later, another car leaves san diego traveling toward LA at a constant speed of 55 mph. After what time is the distance between the cars 15 miles? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #338327 by </B><A HREF=/tutors/aboutme.mpl?userid=geetha_rama><B>geetha_rama(94)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=geetha_rama><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=338327\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let Speed of Car A = 40mph (which leaves at 1:00PM)<BR>\n" );
document.write( "Let Speed of Car B = 55mph  (which leave at 1:30PM)\r<BR>\n" );
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document.write( "Distance the car A would have covered in 30 mins = 40 * 30/60 = 20 miles.\r<BR>\n" );
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document.write( "At 1:30, Car A would be 20 miles from San diego and Car B at San diego.<BR>\n" );
document.write( "Assume after time t, the distance between the two cars is 15 miles\r<BR>\n" );
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document.write( "Distance covered in time t by Car A = 40t + 20miles  (distance covered from 1 to 1:30 PM)\r<BR>\n" );
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document.write( "Distance covered in time t by Car B = 55t\r<BR>\n" );
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document.write( "40t + 20 - 55t = 15 miles (distance between both cars is 15 miles)<BR>\n" );
document.write( "-15t = -5<BR>\n" );
document.write( "t = 1/3 hrs<BR>\n" );
document.write( "   = 1/3 * 60 = 20 mins\r<BR>\n" );
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document.write( "Hence the time is 1:30 + 20 mins = 1:50 PM <BR>\n" );
document.write( "At 1:50PM the distance between two cars will be 15 miles\r<BR>\n" );
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document.write( "CHECK:: Distance covered by Car A (which starts at time 1:00PM ) <BR>\n" );
document.write( "= 40*(1/2+1/3) = 40*5/6 = 200/6 = 100/3 miles<BR>\n" );
document.write( "Distance covered by car B (starting at 1:30PM) = 55*1/3 = 55/3 miles<BR>\n" );
document.write( "Difference in the distance = 100/3 - 55/3 = 45/3 = 15 miles<BR>\n" );
document.write( "   </SPAN>\n" );
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