document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=751870>Question 751870</A>: <I><SPAN STYLE=\"word-break: break-all;\"> We wish to estimate the prevalence of asthma at a large school of 1700 children.  We think it will be around 15% and want a sample size that allows the 99% confidence limits to be within 5% of our final estimate.  TO THE NEAREST 10 CHILDREN (no decimal places), what is the minimum sample size expected to achieve this? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #457544 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=457544\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We wish to estimate the prevalence of asthma at a large school of 1700 children.  We think it will be around 15% and want a sample size that allows the 99% confidence limits to be within 5% of our final estimate.  TO THE NEAREST 10 CHILDREN (no decimal places), what is the minimum sample size expected to achieve this?<BR>\n" );
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document.write( "n = [z/E]^2*pq<BR>\n" );
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document.write( "n = [2.5758/0.05]^2*0.15*0.85 = 338<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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