document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=824306>Question 824306</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Cud you help me solve this question\r<BR>\n" );
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document.write( "An urn contains 9 blue, 7 white and 4 black balls. If 2 balls are drawn at random, then what is the probability that only one ball is white?\r<BR>\n" );
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document.write( "Many thanks... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #496284 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=496284\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Cud you help me solve this question <BR>\n" );
document.write( "An urn contains 9 blue, 7 white and 4 black balls. If 2 balls are drawn at random, then what is the probability that only one ball is white? <BR>\n" );
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document.write( "One Method::<BR>\n" );
document.write( "# of ways to succeed: 7*13 = 91<BR>\n" );
document.write( "# of random pairs: 20C2 = 190<BR>\n" );
document.write( "P(one white) = 91/190<BR>\n" );
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document.write( "A Second Method::<BR>\n" );
document.write( "P(2 white) = 7C2/20C2 = 21/190<BR>\n" );
document.write( "P(2non-white) = 13C2/20C2 = 78/190<BR>\n" );
document.write( "P(one white) = 1 - [(21+78)/20C2] = 1 - 99/190 = 91/190<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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