document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1084400>Question 1084400</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For safety reasons, four different alarm systems were installed in the vault containing the safety deposit boxes at a Beverly Hills bank. Each of the four systems will fail to detect theft with a probability of .01 independently of the others.The bank, obviously, is interested in the probability that when a theft occurs, at least one of the four systems will fail to detect it. This probability is equal to: \r<BR>\n" );
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document.write( "   (.99)^4 \r<BR>\n" );
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document.write( "   1 - (.99)^4 \r<BR>\n" );
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document.write( "   (.01)^4 \r<BR>\n" );
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document.write( "   1 - (.01)^4 \r<BR>\n" );
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document.write( "   none of these <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #698517 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=698517\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Pr(at least one systems fail to detect theft)  = 1 - P(none of the systems fail to detect theft)\r<BR>\n" );
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document.write( "P(none of the systems fail to detect theft) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%280.99%29%5E4+ ALIGN=MIDDLE  ALT=\"+%280.99%29%5E4+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So the answer is  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1-%280.99%29%5E4+ ALIGN=MIDDLE  ALT=\"+1-%280.99%29%5E4+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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