document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1091936>Question 1091936</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A random sample of 22 people employed by the Florida state authority established they earned an average wage (including benefits) of $61.00 per hour. The sample standard deviation was $5.66 per hour. (Use  t Distribution Table.)<BR>\n" );
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document.write( "a.	What is the best estimate of the population mean?<BR>\n" );
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document.write( "  Estimated population mean	$ <BR>\n" );
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document.write( "b.	<BR>\n" );
document.write( "Develop a 98% confidence interval for the population mean wage (including benefits) for these employees. (Round your answers to 2 decimal places.)<BR>\n" );
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document.write( "  Confidence interval for the population mean wage is between <BR>\n" );
document.write( " and <BR>\n" );
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document.write( "c.	<BR>\n" );
document.write( "How large a sample is needed to assess the population mean with an allowable error of $1.00 at 95% confidence? (Round up your answer to the next whole number.)<BR>\n" );
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document.write( "  Sample size	<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #706997 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=706997\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The best estimate of the population mean is $61, the sample mean.<BR>\n" );
document.write( "98% CI is 61+/-t df=21,0.99*5.66/sqrt(22); the t is 2.52<BR>\n" );
document.write( "the half interval is 3.04, 2.52*5.66/sqrt(22)<BR>\n" );
document.write( "the 98% CI is ($57.96, $63.04)<BR>\n" );
document.write( "use a z since we don't know the t for the sample size. Then check to see if this works.<BR>\n" );
document.write( "half-interval is 1<BR>\n" );
document.write( "z*5.66/sqrt(n)=1, and z is 1.96, so <BR>\n" );
document.write( "1.96*5.66=sqrt (n)<BR>\n" );
document.write( "sqrt(n)=11.09<BR>\n" );
document.write( "n=123.06 or 124<BR>\n" );
document.write( "check to see if this works for t.  It is a little large at 1.006 half interval or (58.994, 61.006)<BR>\n" );
document.write( "if one uses 125, it is +/-1.002.<BR>\n" );
document.write( "n=126 gives an error of +/-0.998\r<BR>\n" );
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