document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=473914>Question 473914</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can I please have some help with process?\r<BR>\n" );
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document.write( "There are 14 freshmen and 7 sophomores in a class. If three students are selected at random, find the probability that two are freshmen and one is a sophomore. (to three decimal places.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #325077 by </B><A HREF=/tutors/aboutme.mpl?userid=Maths68><B>Maths68(1474)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Maths68><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=Maths68><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=325077\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are 14 freshmen and 7 sophomores in a class. If three students are selected at random, find the probability that two are freshmen and one is a sophomore. (to three decimal places.)\r<BR>\n" );
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document.write( "Solution:-<BR>\n" );
document.write( "Solution:- <BR>\n" );
document.write( "Freshmen 2 <BR>\n" );
document.write( "Sophomore 1 <BR>\n" );
document.write( "Total 3 <BR>\n" );
document.write( "Now<BR>\n" );
document.write( "Using nCr=n! /(n-r)! r! <BR>\n" );
document.write( "3 students can be chosen out of 21 = 21C3 ways.<BR>\n" );
document.write( "= 21!/(21-3)!3!<BR>\n" );
document.write( "= 21!/ 18!3!<BR>\n" );
document.write( "=(21*20*19*18!) / (18! * 3*2*1)<BR>\n" );
document.write( "= (21*20*19) /(3*2*1)<BR>\n" );
document.write( "= 7980/6<BR>\n" );
document.write( "= 1330 ways<BR>\n" );
document.write( "1 Sophomore can be chosen out of 7 = 7C1 <BR>\n" );
document.write( "= 7! /(7-1)!1!<BR>\n" );
document.write( "=7*6!/6!1!<BR>\n" );
document.write( "= 7 ways <BR>\n" );
document.write( "2 Freshmen can be chosen out of 14 = 14C2<BR>\n" );
document.write( "=14!/(14-2)!2!<BR>\n" );
document.write( "=14!/12!2!<BR>\n" );
document.write( "=14*13*12!/12!2!<BR>\n" );
document.write( "=14*13/2<BR>\n" );
document.write( "=182/2<BR>\n" );
document.write( "=91 ways <BR>\n" );
document.write( "P(1 Sophomore & 2 Freshmen) = (7C1 * 14C2) / 21C3<BR>\n" );
document.write( "= (7*91) /1330 <BR>\n" );
document.write( "=637/1330<BR>\n" );
document.write( "=0.4789<BR>\n" );
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