document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1172465>Question 1172465</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The mean life of stockings used by an army was 40 days with SD of 8 days. Assume the life of stockings follows normal distribution. If 100000 pairs are issued, how many would need replacement (i) before 24 days (ii) after 56 days?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #797502 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=797502\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Before 24 days is a z of -2, where z=(24-40)/8<BR>\n" );
document.write( "probability of that is 0.0228<BR>\n" );
document.write( "number of pair would be 100000*0.0228=2280.  Note, depending upon where one rounds, either table or calculator, the result will be different.\r<BR>\n" );
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document.write( "After 56 days is the same number, because that is more than 2 sd above the mean, and the distribution is symmetrical. </SPAN>\n" );
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