document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=164043>Question 164043</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0029776503/algebrahomeworkh>Introduction to Statistics</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> This question is from Book \" Introduction to Statistics\" By Ronald E. Walpole. 3rd Edition .\r<BR>\n" );
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document.write( "<u><b>Q. 2 (Chapter 4 )pg 105.</b></u>\r<BR>\n" );
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document.write( "A class in advanced physics is comprised of 10 juniors, 30 seniors and 10 graduate students. The final grades showed that 3 of the juniors , 10  of the seniors and 5 of the graduate students received an \"A \" for the course. If a student is chosen at random from this class and is found to have earned an \"A\",<BR>\n" );
document.write( "What is the probability that he or she is a senior?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #120870 by </B><A HREF=/tutors/aboutme.mpl?userid=oscargut><B>oscargut(2103)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oscargut><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=oscargut><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=120870\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P(S/A)= P(S,A)/P(A)\r<BR>\n" );
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document.write( "P(A)=(3+10+5)/(10+30+10)=18/50=9/25<BR>\n" );
document.write( "P(S,A)=10/50=1/5\r<BR>\n" );
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document.write( "then P(S/A)=(1/5)/(9/25)=5/9<BR>\n" );
document.write( "Answer: 5/9 </SPAN>\n" );
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