document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=946484>Question 946484</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I've been stuck on this question on my study guide and i really need to understand how to do it \r<BR>\n" );
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document.write( "An urn contains 4 white balls and 3 green balls. A set of 3 balls are drawn from the urn. Find the probability that the third ball is white given that the first two are white.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #577402 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=577402\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "there are 4 white balls out of 7 in the urn to start with.\r<BR>\n" );
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document.write( "the probability of drawing a white ball on the first draw is therefore 4/7.\r<BR>\n" );
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document.write( "your first draw is a white ball.\r<BR>\n" );
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document.write( "there are 3 white balls out of 6 left in the urn after the first draw.\r<BR>\n" );
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document.write( "the probability of drawing a white ball on the second draw is therefore 3/6.\r<BR>\n" );
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document.write( "your second draw is a white ball.\r<BR>\n" );
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document.write( "there are 2 white balls out of 5 left in the urn after the second draw.\r<BR>\n" );
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document.write( "the probability of drawing a white ball on the third draw is therefore 2/5.\r<BR>\n" );
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document.write( "given that you drew a white ball on the first 2 draws, the probability of drawing a white ball on the third draw is 2/5 because there are 2 white balls left out of a total of 5 balls left in the urn.\r<BR>\n" );
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document.write( "that's my understanding.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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