document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=55312>Question 55312</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is a Poisson probability distribution problem. I thought it was easy but I can't get the answer right. I hope you'll find time to help me. Thanks.\r<BR>\n" );
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document.write( "A Statistics Professor finds that when she schedules an office hour for student help, an average of 2 students arrive. Find the the probability that in a randomly selected hour, the number of student arrival is 5. Give the answer as a decimal value with 4 places of precision and no leading 0.\r<BR>\n" );
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document.write( "P(x) = 2/8 = 0.25  ( I used 8 as I thought it meant 8 office hours)\r<BR>\n" );
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document.write( "P(x) = (0.25)^2 * 2.71828^-0.25/5!\r<BR>\n" );
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document.write( "     = 0.0625 * .779/120\r<BR>\n" );
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document.write( "     = .0004057 (or should it be  .4057)\r<BR>\n" );
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document.write( "Again, thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #37540 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=37540\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I'm using the following formula:<BR>\n" );
document.write( "P(n,T) =(mu*T)^n][e^(-muT)]/n!<BR>\n" );
document.write( "Your mu is 2; your T = 1 hr. ; your n=5<BR>\n" );
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document.write( "Actual arrivals in one hour were 2.<BR>\n" );
document.write( "P(5 arrivals in one hour) = (2(1))^5 e^(-2(1))/5!<BR>\n" );
document.write( "=[32e^-2]/120<BR>\n" );
document.write( "=[32]/[120e^2]<BR>\n" );
document.write( "=0.0361<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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