document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1173584>Question 1173584</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Betty has 20 different books.<BR>\n" );
document.write( "A. If 4 books are selected from these 20 books, how many combinations are there?<BR>\n" );
document.write( "B. Among the 20 books, 12 are classic novels, 6 are science fictions, and 2 are reference books. If 7 classic novels, 2 science fictions, and 1 reference book are selected, how many combinations are there? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #798826 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=798826\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a. This is 20C4=4845 ways<BR>\n" );
document.write( "b. This will be: 12C7 for the first * 6C2 for the second*2C1 for the third<BR>\n" );
document.write( "=792*15*2=23,760 ways. </SPAN>\n" );
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