document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=477685>Question 477685</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Four marbles are selected, one at a time from a bin of marbles containing 6 black, 6 red and 6 green marbles. Let x represent the number of green marbles drawn in 4 draws. <BR>\n" );
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document.write( "(A)  If this experiment is completed without replacing the marbles, explain why x is not a binomial random variable.<BR>\n" );
document.write( "(B)  If this experiment is completed with replacement of the marbles, explain why x is a binomial random variable.<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 #327354 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=327354\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (A) If without replacement, X is not a binomial random variable, because the probability p for should not change after after every trial. The change in the value of p comes from the lack of independence of the trials due to non-replacement.\r<BR>\n" );
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document.write( "(B) If there is replacement, then the trials are independent, and the probability of getting a green marble is 6/18 = 1/3 throughout the experiment. </SPAN>\n" );
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