document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1008340>Question 1008340</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A simple random sample of 40 items resulted in a sample mean of 25. The population standard deviation is 5.<BR>\n" );
document.write( "a. What is the standard deviation of the mean?<BR>\n" );
document.write( "b. At 90% confidence, what is the margin of error?<BR>\n" );
document.write( "c. What is 90% confidence interval estimate for the population mean?<BR>\n" );
document.write( "d. At 95% confidence, what is the margin of error?<BR>\n" );
document.write( "e. What is 95% confidence interval estimate for the population mean? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #624088 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=624088\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  A simple random sample of 40 items resulted in a sample mean of 25. The population standard deviation is 5.<BR>\n" );
document.write( "a. What is the standard deviation of the sample means?:: 5/sqrt(40)<BR>\n" );
document.write( "-----------------------<BR>\n" );
document.write( "b. At 90% confidence, what is the margin of error?<BR>\n" );
document.write( "ME = 1.645*5/sqrt(40) <BR>\n" );
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document.write( "c. What is 90% confidence interval estimate for the population mean?<BR>\n" );
document.write( "25- ME < u < 25+ME<BR>\n" );
document.write( "---------------------------------<BR>\n" );
document.write( "d. At 95% confidence, what is the margin of error?<BR>\n" );
document.write( "ME = 1.96*5/sqrt(40)<BR>\n" );
document.write( "----------------------------<BR>\n" );
document.write( "e. What is 95% confidence interval estimate for the population mean?<BR>\n" );
document.write( "25-ME < u < 25+ME<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );