document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=628336>Question 628336</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a car is going 85mph in 4.5 miles how fast would a stopped car have to go to catch up. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #395585 by </B><A HREF=/tutors/aboutme.mpl?userid=MrLarame><B>MrLarame(2)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MrLarame><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=395585\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I assume you mean that the car travelling at 85 mph can only cover 4.5 miles before the stopped car catches it?\r<BR>\n" );
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document.write( "In that case:<BR>\n" );
document.write( "85mph = 1.25 mi per minute  (85 / 60)\r<BR>\n" );
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document.write( "Since Distance = Rate * Time, we can say: 4.5mi = x mins * 1.25 mi/min, and solve for \"x\" by dividing both sides by 1.25mi/min:<BR>\n" );
document.write( "(4.5mi) / (1.25mi/min) = (3.6 mins)\r<BR>\n" );
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document.write( "So the stopped car needs to accelerate fast enough that it can go the same distance in 3:36 minutes as the car already travelling at 80mph does.\r<BR>\n" );
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document.write( "How fast that is would depend on the acceleration of the stopped car.<BR>\n" );
document.write( "If it could accelerate instantly, it would only need to go 85.0000001 mph! (or any other speed greater than 85)<BR>\n" );
document.write( "If we assume it is a state patrolman with an interceptor, and he can accelerate to 90mph in 15secs, then he'd still have 3:26 to make up the 10 secs worth of distance you went in the meantime (apx 1/3 mile).<BR>\n" );
document.write( "Since he'd be catching up by 5miles each hour, that would be 5/60 or 1/12 mile per minute, so it would take apx 4 mins to make up the 1/3 mile.\r<BR>\n" );
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document.write( "Sounds like he'd probably need to drive apx 95 mph, assuming he \"got on it\" right away.\r<BR>\n" );
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document.write( "There are a lot of variables here though that are not being taken into account, so this is just an \"educated guess!\" </SPAN>\n" );
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