document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1162481>Question 1162481</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A committee of three people is selected at random from a set consisting of <BR>\n" );
document.write( "six ​teachers, \r<BR>\n" );
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document.write( "three parents of​ students, and \r<BR>\n" );
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document.write( "four alumni.\r<BR>\n" );
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document.write( "a. What is the probability of the event that the committee consists of all​ teachers?<BR>\n" );
document.write( "b. What is the probability of the event that the committee consists of all​ parents?<BR>\n" );
document.write( "c. What is the probability of the event that there will be at least 1 teacher on the​ committee? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #786292 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=786292\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> for 3 teachers, easiest way, if one doesn't like combinatorial notation, is (6/13) for first (5/12) for second and (4/11) for third=120/1716=0.0699\r<BR>\n" );
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document.write( "also is (6C3)/(13C3) =20/286=0.0699\r<BR>\n" );
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document.write( "for all parents it is (4C3)/(13C3)=4/286=0.0140\r<BR>\n" );
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document.write( "At least 1 teacher on committee<BR>\n" );
document.write( "do it with 0 teachers on committee and then subtract from 1<BR>\n" );
document.write( "(7C3)/(13C3)=35/286=0.1224. looking at a committee of all parents or alumni<BR>\n" );
document.write( "so the answer with at least 1 teacher is 1-0.1224 or 0.8776. </SPAN>\n" );
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