document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1121476>Question 1121476</A>: <I><SPAN STYLE=\"word-break: break-all;\"> People were polled on how many books they read the previous year. How many subjects are needed to estimate the number of books read the previous year within one book with 95&#8203;% &#8203;confidence? Initial survey results indicate that sigmaequals19.5 books.<BR>\n" );
document.write( "A 95 % confidence level requires <BR>\n" );
document.write( "nothing subjects. <BR>\n" );
document.write( "&#8203;(Round up to the nearest whole number as&#8203; needed.)<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #737423 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=737423\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> use z first and then change to t<BR>\n" );
document.write( "half interval is z*sigma/sqrt(n)=1.96*19.5/sqrt(n) and that equals 1<BR>\n" );
document.write( "multiply by sqrt (n) and then square both sides<BR>\n" );
document.write( "3.84^2*19.5^2=1460.77 or 1461 ANSWER<BR>\n" );
document.write( "This will be the same for t or z. </SPAN>\n" );
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