document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1178274>Question 1178274</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How large should the size of a random sample be so that we can be 90% certain that the sample mean X will not deviate from the true mean by more than σ/2?\r<BR>\n" );
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document.write( "thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #807572 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=807572\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  90% certain:  z = 1.645<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29+=+ME%2A+sqrt%28n%29%2Fblue%28sigma%29+ ALIGN=MIDDLE  ALT=\"z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29+=+ME%2A+sqrt%28n%29%2Fblue%28sigma%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >     <BR>\n" );
document.write( "0r<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+n+=+%28+z%2Asigma%2FME%29%5E2+=+%281.645%2Asigma%2F%28sigma%2F2%29%29%5E2++=+2.706%2A4+=+10.8241 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "n = 11  (rounding up to next whole number)  </SPAN>\n" );
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