document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=204089>Question 204089</A>: <I><SPAN STYLE=\"word-break: break-all;\"> determine how many card holders should be sampled.\r<BR>\n" );
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document.write( "what is the required sample size needed to be able to estimate the mean dollars that credit card holders will spend each month.  Within plus or minus $10.00 of the true mean with a 98% confidence level?  Standard deviation is thought to be $500.00.  how many card holders should be sampled?  We then find out  it will cost $5.00 per sample and the company is only planning to spend $10,000.00 on the sample.  What will the trade off be when you lower the sample to $10,000.00 to meet their budget? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #154024 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=154024\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> determine how many card holders should be sampled. <BR>\n" );
document.write( "what is the required sample size needed to be able to estimate the mean dollars that credit card holders will spend each month. Within plus or minus $10.00 of the true mean with a 98% confidence level? Standard deviation is thought to be $500.00. how many card holders should be sampled? We then find out it will cost $5.00 per sample and the company is only planning to spend $10,000.00 on the sample. What will the trade off be when you lower the sample to $10,000.00 to meet their budget<BR>\n" );
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document.write( "n = [z*s/E]^2<BR>\n" );
document.write( "n = [2.0537*500/10]^2 = 102.69^2 = 10544.7<BR>\n" );
document.write( "Rounded up you get n = 10545<BR>\n" );
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document.write( "If you lower the sample size the confidence level will decrease<BR>\n" );
document.write( "or the margin of error will increase or both will happen.<BR>\n" );
document.write( "That is because sample size and z* are directly related and<BR>\n" );
document.write( "sample size and E are inversely related.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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