document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1152816>Question 1152816</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The probability of a randomly selected adult in one country being infected with a certain virus is 0.005. In tests for the​ virus, blood samples from 24 people are combined. What is the probability that the combined sample tests positive for the​ virus? Is it unlikely for such a combined sample to test​ positive? Note that the combined sample tests positive if at least one person has the virus. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #774891 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=774891\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is 0.995 probability that an adult will not test positive.<BR>\n" );
document.write( "For combining 24 people, assuming independence, the probability of not testing positive is now 0.995^24=0.8867\r<BR>\n" );
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document.write( "so the answer to the first is the complement or 0.1133<BR>\n" );
document.write( "That would not be considered unlikely, although the word's definition would need to be clarified.  With a rare disease (1/2000) to have a 1/10 probability of being positive represents a considerable degrading of the test. </SPAN>\n" );
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