document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=711487>Question 711487</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a box contains 4 white balls, one black ball and seven red balls. how many white balls must be added to the box so that the probability of drawing a white ball is 2/3 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #437435 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=437435\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a box contains 4 white balls, one black ball and seven red balls. how many white balls must be added to the box so that the probability of drawing a white ball is 2/3<BR>\n" );
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document.write( "# of white balls: 4 + x<BR>\n" );
document.write( "Total # of balls (4 + 1 + 7 + x) = 12+x<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "(4+x)/(12+ x) = 2/3<BR>\n" );
document.write( "12+3x = 24+2x<BR>\n" );
document.write( "x = 12 (# of white balls to add to the box)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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