document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=973108>Question 973108</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An editor wants to estimate average the number of pages in bestselling novels, so that his estimate falls within 25 pages of the true average. Assuming that the standard deviation is 65 pages, how large a sample of bestselling novels is needed to achieve  ( 15 points) \r<BR>\n" );
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document.write( "a) 99% confident  \r<BR>\n" );
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document.write( "b) 95% confident \r<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 #595353 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=595353\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An editor wants to estimate average the number of pages in bestselling novels, so that his estimate falls within 25 pages of the true average. Assuming that the standard deviation is 65 pages, how large a sample of bestselling novels is needed to achieve ( 15 points) <BR>\n" );
document.write( "a) 99% confident<BR>\n" );
document.write( "n = [2.5758*65/25]^2 = 45 when rounded up<BR>\n" );
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document.write( "b) 95% confident<BR>\n" );
document.write( "n = [1.96*65/25]^2 = 26 when rounded up<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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