document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1194470>Question 1194470</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please assist me in solving this question below<BR>\n" );
document.write( "A vaccine has a 90% probability of being effective in preventing a certain<BR>\n" );
document.write( "disease. The probability of getting the disease if a<BR>\n" );
document.write( "person is not vaccinated is 50%. In a certain geographic<BR>\n" );
document.write( "region, 25% of the people get vaccinated. If a person is<BR>\n" );
document.write( "selected at random, find the probability that he or she<BR>\n" );
document.write( "will contract the disease. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #826680 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52790)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=826680\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Please assist me in solving this question below<BR>\n" );
document.write( "A vaccine has a 90% probability of being effective in preventing a certain<BR>\n" );
document.write( "disease. The probability of getting the disease if a<BR>\n" );
document.write( "person is not vaccinated is 50%. In a certain geographic<BR>\n" );
document.write( "region, 25% of the people get vaccinated. If a person is<BR>\n" );
document.write( "selected at random, find the probability that he or she<BR>\n" );
document.write( "will contract the disease.<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "If a person is selected at random, then EITHER\r\n" );
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document.write( "    (a) the probability that he or she was not vaccinated is 75%, \r\n" );
document.write( "        and then the probability for such a person to get a disease is 50%;\r\n" );
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document.write( "OR\r\n" );
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document.write( "    (b) the probability that he or she was vaccinated is 25%,\r\n" );
document.write( "        and then the probability for such a person to get a disease is 100%-90% = 10%.\r\n" );
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document.write( "Taking it into account, the probability that a person selected at random\r\n" );
document.write( "will contract the disease is\r\n" );
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document.write( "    P = 0.75*0.5 + 0.25*0.1 = 0.4.    <U>ANSWER</U>\r\n" );
document.write( "</PRE>\r<BR>\n" );
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document.write( "Solved.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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