document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=80420>Question 80420</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a nurse at a local hospital is estimating the weight of infants. how large a sample must she select if she desires to be 95% confident that the true mean is within 3 ounces of the sample mean? sd=7 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #57701 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=57701\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a nurse at a local hospital is estimating the weight of infants. how large a sample must she select if she desires to be 95% confident that the true mean is within 3 ounces of the sample mean? sd=7<BR>\n" );
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document.write( "E = z*sigma/sqrt(n)<BR>\n" );
document.write( "sqrt(n) = z*sigma/E<BR>\n" );
document.write( "Your Problem:<BR>\n" );
document.write( "sqrt(n) = 1.96*7/3<BR>\n" );
document.write( "sqrt(n) = 4.57333<BR>\n" );
document.write( "n= 20.91..<BR>\n" );
document.write( "Rounding up: n=21<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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