document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=629789>Question 629789</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a box contains 8 white balls, 4 black balls, and 9 red balls.<BR>\n" );
document.write( "how many red balls must be added to the box so that the probability of drawing a red ball is 2/3 ?<BR>\n" );
document.write( "how many black balls must be added to the original box so that the probability of drawing a white ball is 1/3 ? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #396493 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=396493\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a box contains 8 white balls, 4 black balls, and 9 red balls.<BR>\n" );
document.write( "total of 21 balls<BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "how many red balls must be added to the box so that the probability of drawing a red ball is 2/3 ?<BR>\n" );
document.write( "Let the number added be \"x\".<BR>\n" );
document.write( "Equation:<BR>\n" );
document.write( "(9+x)/(21+x) = 2/3<BR>\n" );
document.write( "3(9+x) = 2(21+x)<BR>\n" );
document.write( "27 + 3x = 42+2x<BR>\n" );
document.write( "x = 15<BR>\n" );
document.write( "----------------------------------<BR>\n" );
document.write( "how many black balls must be added to the original box so that the probability of drawing a white ball is 1/3 ?<BR>\n" );
document.write( "Let the number be \"x\":<BR>\n" );
document.write( "8/(21+x) = 1/3<BR>\n" );
document.write( "21+x = 24<BR>\n" );
document.write( "x = 3<BR>\n" );
document.write( "==============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );