document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1042799>Question 1042799</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Some drug tests are about 90% reliable. This means that there is a probability of 0.9 that the test will correctly identify a drug user or a nonuser. To be safe, each person is tested twice. What is the probability that a drug user will fail at least one of the tests? (Round your answer to four decimal places.)  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #657877 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=657877\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Some drug tests are about 90% reliable. This means that there is a probability of 0.9 that the test will correctly identify a drug user or a nonuser. To be safe, each person is tested twice. What is the probability that a drug user will fail at least one of the tests? (Round your answer to four decimal places.)<BR>\n" );
document.write( "--------<BR>\n" );
document.write( "P(fail >= 1 test) = 1 - P(pass both) = 1-0.9^2 = 1-0.81 = 0.19<BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "----------- <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );