document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=240040>Question 240040</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the dample size required to estimate the maen age of required drivers in the United States. Assume that we want 95% confidence that the sample mean is within 1/2 yera of the true mean asge of the population. Also assume that the standard deviation of the population is known to be 12 years. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #175992 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=175992\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the sample size required to estimate the mean age of required drivers in the United States. Assume that we want 95% confidence that the sample mean is within 1/2 year of the true mean age of the population. Also assume that the standard deviation of the population is known to be 12 years.<BR>\n" );
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document.write( "n = [z*s/E]^2<BR>\n" );
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document.write( "n = [1.96*12/(1/2)]^2 = 2212.76<BR>\n" );
document.write( "Rounding up n = 2213<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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