document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1122116>Question 1122116</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need your help on the following:\r<BR>\n" );
document.write( "\n" );
document.write( "A.	A child chosen at random in a community school system comes from a low-income family 15 percent of the time. Children from low-income families in the community graduate from college only 20 percent of the time. Children not from low-income families have a 40 percent chance of graduating from college. As an employer of people from this community, you are reviewing applicants and note that the first one had a college degree. What is the probability that the person comes from low-income family?<BR>\n" );
document.write( "B.	By very carefully screening applicants, the Bank of Halifax Country has been able to limit bad-debt losses on consumer loans to 8 percent. What is the probability that at least four of the five loan  applicants that you, as a loan officer trainee, have just approved will repay their loans?<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #738188 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52903)</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=738188\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "I came to fix the solution to Problem A given by the tutor @rothauserc, which is wrong.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "We have to interpret the condition in this way:\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
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( "    15% of children in a community school system come from low-income families \r\n" );
document.write( "    and the rest  100%-15% = 85%  come from not low-income families.\r\n" );
document.write( "</PRE>\r<BR>\n" );
document.write( "\n" );
document.write( "Now, the problem asks what is the probability that the applicant having a college degree comes from a low income family.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "It is the \"conditional\" probability.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "So the solution is\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
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( "    the probability under the question is  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%280.15%2A0.2%29%2F%280.15%2A0.2+%2B+0.85%2A0.4%29 ALIGN=MIDDLE  ALT=\"%280.15%2A0.2%29%2F%280.15%2A0.2+%2B+0.85%2A0.4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > =  0.081081 = 8.1%  (approximately).\r\n" );
document.write( "</PRE>\r<BR>\n" );
document.write( "\n" );
document.write( "The denominator is the probability that the applicant has a college degree.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Solved.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );