document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1142523>Question 1142523</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A researcher wanting to investigate the prevalence of smoking among teens selected a random sample of 200 teens and asked whether or not they smoked. This information is recorded in the following table:\r<BR>\n" );
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document.write( "                   Yes      No<BR>\n" );
document.write( "        Male    38      82<BR>\n" );
document.write( "    Female    24      56\r<BR>\n" );
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document.write( "a) What is the probability of randomly selecting a teen that is female? <BR>\n" );
document.write( "b) What is the probability of randomly selecting a teen that is female and smokes?<BR>\n" );
document.write( "c) What is the probability of randomly selecting a teen that smokes given that he is<BR>\n" );
document.write( "male? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #763208 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=763208\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "a) From the basic definition of probability,<br><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( "      number of females\r\n" );
document.write( "  --------------------------\r\n" );
document.write( "  total number in the sample<br></PRE><BR>\n" );
document.write( "b) From the same definition,<br><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( "   number of females who smoke\r\n" );
document.write( "  -----------------------------\r\n" );
document.write( "   total number in the sample<br></PRE><BR>\n" );
document.write( "c) With the condition \"given that he is a male\", the denominator of the probability fraction is only the number of males in the sample:<br><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( "    number of males who smoke\r\n" );
document.write( "   ---------------------------\r\n" );
document.write( "     total number of males<br></PRE> </SPAN>\n" );
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