document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1093511>Question 1093511</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A smoke detector system uses two devices A and B. If smoke is present the<BR>\n" );
document.write( "probability that it will be detected by device A is 0.95, by device B 0.9 and by<BR>\n" );
document.write( "both devices 0.88. \r<BR>\n" );
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document.write( "a) suppose, before checking the devices, there is a 15% chance of smoke. calculate the probability <BR>\n" );
document.write( " that there is smoke given that B didn't detect smoke\r<BR>\n" );
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document.write( "b) repeat part a), now given that neither A or B detected smoke </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #708254 by </B><A HREF=/tutors/aboutme.mpl?userid=ciaV><B>ciaV(1)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ciaV><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=708254\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a) .1(.15) = .015\r<BR>\n" );
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document.write( ".1 = the percentage that B does not detect so that times the the percentage that there is smoke\r<BR>\n" );
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document.write( "b) .1(.05)(.15) =7.5 x 10^-4 <BR>\n" );
document.write( ".1 = B does not detect<BR>\n" );
document.write( ".05= A does not detect <BR>\n" );
document.write( " times the percentage that there is smoke </SPAN>\n" );
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