document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=349170>Question 349170</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Intersection and conditional probability <BR>\n" );
document.write( "Suppose that a certain college class contains 64 students. Of these,35  are juniors, 34 are history majors, and 9 are neither. A student is selected at random from the class. \r<BR>\n" );
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document.write( "(a) What is the probability that the student is both a junior and a history major? <BR>\n" );
document.write( "(b) Given that the student selected is a history major, what is the probability that she is also a junior?<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 #249623 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=249623\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Intersection and conditional probability <BR>\n" );
document.write( "Suppose that a certain college class contains 64 students. Of these,35 are juniors, 34 are history majors, and 9 are neither. A student is selected at random from the class. <BR>\n" );
document.write( "(a) What is the probability that the student is both a junior and a history major? <BR>\n" );
document.write( "p(jun AND hm) = 24/45<BR>\n" );
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document.write( "(b) Given that the student selected is a history major, what is the probability that she is also a junior?<BR>\n" );
document.write( "P(j|hm) = 24/34<BR>\n" );
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document.write( "Draw a Venn diagram with two intersecting circles: j and hm<BR>\n" );
document.write( "Procedure <BR>\n" );
document.write( "The number of students in j+(j AND hm)+ hm = 45 - (j AND hm)<BR>\n" );
document.write( "Let # in (j AND hm) = x<BR>\n" );
document.write( "Then # if j but not in j AND m = 35-x<BR>\n" );
document.write( "And # in hm but not in j AND m = 34-x<BR>\n" );
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document.write( "Solve for \"x\".<BR>\n" );
document.write( "I get x = 24<BR>\n" );
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document.write( "From that you can figure out the propabilities.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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