document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=182563>Question 182563</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need some help solving this problem..\r<BR>\n" );
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document.write( "USE THE NORMAL APPROXIMATION OF THE BINOMIAL PROBABILITY<BR>\n" );
document.write( "DISTRIBUTION TO SOLVE THE PROBLEM BELOW.\r<BR>\n" );
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document.write( "DeKorte Telemarketing Inc. is considering purchasing a machine that randomly<BR>\n" );
document.write( "selects and automatically dials telephone numbers. It makes most of its calls<BR>\n" );
document.write( "during the evening, so calls to business phones are wasted. The manufacturer of<BR>\n" );
document.write( "the machine claims that their programming reduces the calling to business phones<BR>\n" );
document.write( "to 15 percent of all calls. To test this claim, the Director of Purchasing at<BR>\n" );
document.write( "DeKorte programmed the machine to select a sample of 150 phone numbers.<BR>\n" );
document.write( "What is the probability that more than 30 of the phone selected are that of a<BR>\n" );
document.write( "business, assuming the manufacturer’s claim is correct? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #137067 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=137067\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> USE THE NORMAL APPROXIMATION OF THE BINOMIAL PROBABILITY<BR>\n" );
document.write( "DISTRIBUTION TO SOLVE THE PROBLEM BELOW. <BR>\n" );
document.write( "DeKorte Telemarketing Inc. is considering purchasing a machine that randomly<BR>\n" );
document.write( "selects and automatically dials telephone numbers. It makes most of its calls<BR>\n" );
document.write( "during the evening, so calls to business phones are wasted. The manufacturer of<BR>\n" );
document.write( "the machine claims that their programming reduces the calling to business phones<BR>\n" );
document.write( "to 15 percent of all calls. To test this claim, the Director of Purchasing at<BR>\n" );
document.write( "DeKorte programmed the machine to select a sample of 150 phone numbers.<BR>\n" );
document.write( "What is the probability that more than 30 of the phone selected are that of a<BR>\n" );
document.write( "business, assuming the manufacturer’s claim is correct?<BR>\n" );
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document.write( "u = np = 150*0.15 = 22.5<BR>\n" );
document.write( "sigma = sqrt(npq) = sqrt(22.5*0.85) = sqrt(19.125) = 4.373<BR>\n" );
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document.write( "Normal Approx Approach:<BR>\n" );
document.write( "P(31 < x <= 150) = normal cdf(31,150,22.5,4.373) = 0.324...<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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