document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1119229>Question 1119229</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A bag contains 2 red, 1 black and 1 white ball. Peter selects one ball from the bag. He then selects a second ball but does not replace the first ball before the second ball is chosen.<BR>\n" );
document.write( "a) draw a diagram showing all possibilities<BR>\n" );
document.write( "b) find the probability that i) both balls selected are red ii) at least one selected ball is red <BR>\n" );
document.write( "c) What is the probability that Peter had two red balls if it is known that at least one ball was red? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #734722 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=734722\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Red2 Black 1 White 1<BR>\n" );
document.write( "R-R probability is 1/2*1/3=1/6<BR>\n" );
document.write( "R-B probability is 1/2*1/3=1/6<BR>\n" );
document.write( "R-W probability is also 1/6<BR>\n" );
document.write( "B-R probability is 1/4*2/3=1/6<BR>\n" );
document.write( "B-W probability is 1/4*1/3=1/12<BR>\n" );
document.write( "W-R probability is 1/6<BR>\n" );
document.write( "W-B probability is 1/12\r<BR>\n" );
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document.write( "b. Both are red has probability 1/3<BR>\n" );
document.write( "At least one is red has probability is 5/6<BR>\n" );
document.write( "c.  If one ball is red (probability 1/2), both are red has probability 1/3, since if 1 is red, there are three other balls with three different colors, one of which is red, and that probability is 1/3<BR>\n" );
document.write( " </SPAN>\n" );
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