document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=331510>Question 331510</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One-hour carbon monoxide concentrations in air samples from a large city have an approximately exponential distribution with mean 3.6 ppm (parts per million).<BR>\n" );
document.write( "a, find the probability that the carbon monoxide concentration exceeds 9 ppm during a randomly selected one-hour period.<BR>\n" );
document.write( "b, a traffic-control strategy reduced the mean to 2.5 ppm. Now find the probability that the concentration exceeds 9 ppm. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #237663 by </B><A HREF=/tutors/aboutme.mpl?userid=jrfrunner><B>jrfrunner(365)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jrfrunner><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=jrfrunner><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=237663\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> if x is exponentially distributed then \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=fx+=+%281%2Fmu%29+%2Ae%5E%28-x%2Fmu%29 ALIGN=MIDDLE  ALT=\"fx+=+%281%2Fmu%29+%2Ae%5E%28-x%2Fmu%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+P%29x%3Ea%29+=+e%5E%28-a%2Fmu%29 ALIGN=MIDDLE  ALT=\"+P%29x%3Ea%29+=+e%5E%28-a%2Fmu%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "in part 1, mu=3.6 and a=9  \r<BR>\n" );
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document.write( "so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28x%3E9%29+=+e%5E%28-9%2F3.6%29+=0.082 ALIGN=MIDDLE  ALT=\"P%28x%3E9%29+=+e%5E%28-9%2F3.6%29+=0.082\"   DISABLED_style= \"max-width:90%; height:auto;\" > or 8.25%\r<BR>\n" );
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document.write( "in part 2, mu=2.5 and a =9\r<BR>\n" );
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document.write( "so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28x%3E9%29+=e%5E%28-9%2F2.5%29+=0.0273 ALIGN=MIDDLE  ALT=\"P%28x%3E9%29+=e%5E%28-9%2F2.5%29+=0.0273\"   DISABLED_style= \"max-width:90%; height:auto;\" > or 2.7%  </SPAN>\n" );
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