document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1192024>Question 1192024</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Cinema seats are numbered with those numbers: 1, 2, ..., 20. 6 friends one after another buys tickets and seats are allocated to them at random order. <BR>\n" );
document.write( "a) What are the chances that everyone will get seats with even numbers?<BR>\n" );
document.write( "b) 2 friends that come earlier got seats with even numbers. What are the probability that the rest will also get places with even numbers? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #823915 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=823915\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "(a) At the start, there are 10 even-numbered seats out of a total of 20.<br><BR>\n" );
document.write( "P(1st seat # is even) = 10/20<BR>\n" );
document.write( "P(2nd seat # is even) = 9/19<BR>\n" );
document.write( "...<BR>\n" );
document.write( "P(5th seat # is even) = 6/16<BR>\n" );
document.write( "P(6th seat # is even) = 5/15<br><BR>\n" );
document.write( "You want all those things to happen, so multiply all those probabilities.  I leave it to you to do the calculations and express the result in the required format.<br><BR>\n" );
document.write( "(b) In this case, 2 of the 10 even-numbered seats are already occupied.  The solution process is the same as in part (a); but now the probabilities are 8/18, 7/17, ..., 4/14, and 3/13.<br>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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