document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1076942>Question 1076942</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You plan to construct a 96% percent confidence interval for the true proportion of students who attempted a review quiz more than 4 times. Assume that you will be able to use a Simple Random Sample.\r<BR>\n" );
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document.write( "(a) What is the critical value for such a confidence interval? Give your answer to three decimal places.\r<BR>\n" );
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document.write( "(b) What is the minimum sample size required to get a margin of error less than 0.04?\r<BR>\n" );
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document.write( "n = </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #691532 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=691532\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z=2.053<BR>\n" );
document.write( "for minimum sample size use p=0.5 which maximizes the interval<BR>\n" );
document.write( "0.04=2.053*sqrt(p*(1-p))/n<BR>\n" );
document.write( "square both sides and multiply by n<BR>\n" );
document.write( "0.0016n=1.0537<BR>\n" );
document.write( "n=658.56=659 </SPAN>\n" );
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