document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=299896>Question 299896</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The probability that an employee at the company is over 40 years old is 0.6. If 18 employees are asked heir age, find the probability that a)exactly 3 are over 40 years old, b) at least 9 are over 40 years old, c)fewer than 4 are over 40, find the d) mean, e) variance, f) standard deviation.\r<BR>\n" );
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document.write( "I am pressed for time my professor doesn't really speak understandable english and I dont want to fail his class I understand mostly on my own but a few of my problems I need assistance with pls help if you can. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #215317 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=215317\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The probability that an employee at the company is over 40 years old is 0.6. If 18 employees are asked heir age, find the probability that<BR>\n" );
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document.write( "You need some understanding of technology or of a binomial table<BR>\n" );
document.write( "to get answers for a,b, and c:<BR>\n" );
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document.write( "a)exactly 3 are over 40 years old = P(x=3) = 18C3(0.6)^3*(0.4)^15<BR>\n" );
document.write( "= 0.0001893..<BR>\n" );
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document.write( "b) at least 9 are over 40 years old <BR>\n" );
document.write( "= 1-P(0<= x <=8) = 1-binomcdf(18,0.6,8) = 0.8653<BR>\n" );
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document.write( "c)fewer than 4 are over 40, <BR>\n" );
document.write( "binomcdf(18,0.6,3) = 0.0002148<BR>\n" );
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document.write( " find the <BR>\n" );
document.write( "d) mean = np = 18*0.6 = 10.8 <BR>\n" );
document.write( "e) variance = npq = 10.8*0.4 = 4.32 <BR>\n" );
document.write( "f) standard deviation = sqrt(4.32) = 2.0785<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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