document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=284157>Question 284157</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A survey of 1084 men age 18 & older in 1998 for the Commonwealth Fund indicated that more than half did not have a physical exam or a blood cholesterol test in the past year.  A medical researcher plans to sample men in her community randomly to see if similar results occur.  How large a random sample would she need to estimate this proportion to within .05 with probability 0.95? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #206311 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=206311\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A survey of 1084 men age 18 & older in 1998 for the Commonwealth Fund indicated that more than half did not have a physical exam or a blood cholesterol test in the past year. A medical researcher plans to sample men in her community randomly to see if similar results occur. How large a random sample would she need to estimate this proportion to within .05 with probability 0.95?<BR>\n" );
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document.write( "n = [z/E]^2(p-hat)(q-hat)<BR>\n" );
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document.write( "n = [1.96/0.05]^2*(1/2)(1/2)<BR>\n" );
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document.write( "n = 384.16<BR>\n" );
document.write( "Round up to n = 385<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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