document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1161046>Question 1161046</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Is it D? I want to check my answer.\r<BR>\n" );
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document.write( "A teacher asked students in his class if they had any brothers or sisters. The results are shown below. What is the chance of randomly selecting someone from this group with a brother given that they have a sister? \r<BR>\n" );
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document.write( "P(Brother|Sister) \r<BR>\n" );
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document.write( "A. 5/12\r<BR>\n" );
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document.write( "B. 5/17\r<BR>\n" );
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document.write( "C. 5/9\r<BR>\n" );
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document.write( "D. 5/14\r<BR>\n" );
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document.write( "The Venn diagram for the question and the question itself are provided in the link here: https://i.imgur.com/Y4MOmRK.png </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #784466 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52781)</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=784466\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
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document.write( "The diagram under the link shows, that there are 12 students in the class who have sister/sisters.\r\n" );
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document.write( "We can consider these 12 students as the population's part described by this fragment of the condition\r\n" );
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document.write( "           +------------------------------------+\r\n" );
document.write( "           |  \"given that they have a sister\".  |\r\n" );
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document.write( "Of these 12 students, 5 have a brother/brothers.\r\n" );
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document.write( "Therefore, the probability under the problem's question is  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F12 ALIGN=MIDDLE  ALT=\"5%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r\n" );
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document.write( "The  <U>ANSWER</U>  is option A.\r\n" );
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document.write( "Solved.\r<BR>\n" );
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document.write( "-------------------\r<BR>\n" );
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document.write( "<U>An important post-solution note</U>.\r<BR>\n" );
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document.write( "    The important part is that the brothers or sisters can be not at / (or from) the given class.\r\n" );
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document.write( "    They (the sisters and the brothers) can be from totally different sets outside the class.\r\n" );
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document.write( "    Also, it is important to understand that the circles \"brothers\" and \"sisters\" on Venn  diagram DO NOT REPRESENT the girls or the boys.\r\n" );
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document.write( "    They represent partial populations of the class united according to the principle \"has or not has this feature\".\r\n" );
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document.write( "    It is similar to as if the students in the class were wearing special badges \"have a brother\", or \"have a sister\", OR BOTH (!)\r\n" );
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document.write( "If you understand all of that, &nbsp;it means that you understand the problem &nbsp;ADEQUATELY.\r<BR>\n" );
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document.write( "This problem &nbsp;<U>TEACHES &nbsp;YOU &nbsp;to understand the given description adequately</U>.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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