document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=245770>Question 245770</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An urn contains 3 red and 2 white numbered balls. A sample of 2 balls is randomly chosen. Find the average number of red balls in the sample. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #179480 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=179480\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An urn contains 3 red and 2 white numbered balls. A sample of 2 balls is randomly chosen. Find the average number of red balls in the sample.<BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "Average means \"the expected number\".<BR>\n" );
document.write( "--<BR>\n" );
document.write( "Random variable vales: 0,1,2<BR>\n" );
document.write( "Corresponding probabilities: <BR>\n" );
document.write( "P(x=0) = 3C0/5C2 = 1/10<BR>\n" );
document.write( "P(x=1) = 3C1*2C1/5C2 = 6/10<BR>\n" );
document.write( "P(x=2) = 3C2/5C2 = 3/10<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "E(X) = 0*(1/10) + 1*(6/10) + 2*(3/10) = (0+6+6)/10 = 1.2 red balls<BR>\n" );
document.write( "=======================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );