document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=193188>Question 193188</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The number of accidents per week at a hazardous intersection varies with mean 2.2 and standard deviation 1.4 accidents. This variable is discrete. It is certainly not normaly distributed. Let x-bar be the mean number of accidents per week at the intersection during a year.(52 weeks).\r<BR>\n" );
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document.write( "Question: What is the approximate chance that there are fewer than 130 accidents at the intersection a year? (Restate in terms of x-bar) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #145043 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=145043\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The number of accidents per week at a hazardous intersection varies with mean 2.2 and standard deviation 1.4 accidents. This variable is discrete. It is certainly not normaly distributed. Let x-bar be the mean number of accidents per week at the intersection during a year.(52 weeks). <BR>\n" );
document.write( "Question: What is the approximate chance that there are fewer than 130 accidents at the intersection a year? (Restate in terms of x-bar)<BR>\n" );
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document.write( "130 per year = 130/52 = 2.5 per week<BR>\n" );
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document.write( "(2.5-2.2)/1.4 = 1.78<BR>\n" );
document.write( "So an average of 2.5 accidents perweek is 1.78 standard deviations<BR>\n" );
document.write( "above the mean of 2.2.<BR>\n" );
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document.write( "The appromate chance the average is less than 2.5 accidents per week<BR>\n" );
document.write( "is about 96% or 0.9629...<BR>\n" );
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document.write( "Comment: Those figures are based on the distribution being normal; but<BR>\n" );
document.write( "they are suitable as an approximation.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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