document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=87624>Question 87624</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0918091861/algebrahomeworkh>DISCOVERING STATISTICS</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> 7. The number of violent crimes committed in a large city follows a Poisson distribution with an average rate of 10 per month.<BR>\n" );
document.write( "a. Find the expected number of violent crimes committed in a 3 month period<BR>\n" );
document.write( "b. Find the standard deviation of the number of violent crimes committed in a 3 month period<BR>\n" );
document.write( "c. Find the probability that at least 45 violent crimes will be committed in a 3 month period<BR>\n" );
document.write( "d. Find the probability that between 25 and 40 violent crimes will be committed in a 3 month period<BR>\n" );
document.write( "e. Find the probability that less than 20 violent crimes will be committed in a 3 month period<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #63557 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=63557\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 7. The number of violent crimes committed in a large city follows a Poisson distribution with an average rate of 10 per month.<BR>\n" );
document.write( "a. Find the expected number of violent crimes committed in a 3 month period<BR>\n" );
document.write( "# = 3*10 = 30<BR>\n" );
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document.write( "b. Find the standard deviation of the number of violent crimes committed in a 3 month period<BR>\n" );
document.write( "# = sqrt(30) <BR>\n" );
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document.write( "c. Find the probability that at least 45 violent crimes will be committed in a 3 month period<BR>\n" );
document.write( "P(45,30) = e^-30*30^45/45! = 0.0023<BR>\n" );
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document.write( "d. Find the probability that between 25 and 40 violent crimes will be committed in a 3 month period<BR>\n" );
document.write( "P(45,30)-P(24,30) = poissoncdf(30,45)-Poissoncdf(30,24)=0.8388...<BR>\n" );
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document.write( "e. Find the probability that less than 20 violent crimes will be committed in a 3 month period<BR>\n" );
document.write( "Poissoncdf(30,19)=0.02187...<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "</TD></TR></TABLE>\n" );