document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=924483>Question 924483</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A research firm needs to estimate within 3% the proportion of junior executives leaving large manufacturing companies within three years. A 0.95 degree of confidence is to be used. Several years ago, a study revealed that 21% of junior executives left their company within three years. To update this study, how many junior executives should be surveyed? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #560921 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=560921\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ME = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z%2Asqrt%28%28p%281-p%29%29%2Fn%29 ALIGN=MIDDLE  ALT=\"z%2Asqrt%28%28p%281-p%29%29%2Fn%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "...<BR>\n" );
document.write( "ME = .03<BR>\n" );
document.write( ".95 degree of confidence <BR>\n" );
document.write( "n = p(1-p)(z/ME)^2<BR>\n" );
document.write( "n = (.21)(.79)(1.96/.05)^2 = 255 (rounded to next  Integer)<BR>\n" );
document.write( " </SPAN>\n" );
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