document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=393634>Question 393634</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If 9% of all calculators are defective, find the mean, variance and standard deviation of a lot of 500 calculators. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #279628 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=279628\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let X = r.v. representing the # of defects.\r<BR>\n" );
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document.write( "Then mean is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=mu+=+E%28X%29+=+np+=+500%2A0.09++=45 ALIGN=MIDDLE  ALT=\"mu+=+E%28X%29+=+np+=+500%2A0.09++=45\"   DISABLED_style= \"max-width:90%; height:auto;\" >, variance is \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sigma%5E2+=+npq+=+500%2A0.09%2A0.91++=40.95 ALIGN=MIDDLE  ALT=\"sigma%5E2+=+npq+=+500%2A0.09%2A0.91++=40.95\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and standard deviation is\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sigma+=+sqrt%2840.95%29+=+%283sqrt%28455%29%29%2F10++=6.4 ALIGN=MIDDLE  ALT=\"sigma+=+sqrt%2840.95%29+=+%283sqrt%28455%29%29%2F10++=6.4\"   DISABLED_style= \"max-width:90%; height:auto;\" > to the nearest tenth. </SPAN>\n" );
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