document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=336570>Question 336570</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A jar contains 10 red, 7 blue and 5 yellow marbles. Blue marbles are then added in order to change the probability of randomly selecting a blue marble from the jar to “greater than 1/2”.What is the least number of blue marbles that must be added? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #241259 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=241259\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The probability before adding any blue balls is 10/(10+7+5)=10/22<BR>\n" );
document.write( "Let x be the least number of blue marbles that must be added.<BR>\n" );
document.write( "(10+x)/(22+x) > 1/2<BR>\n" );
document.write( "10+x>(22+x)/2<BR>\n" );
document.write( "20+2x>22+x<BR>\n" );
document.write( "x>2 <BR>\n" );
document.write( "Since x is greater than 2 then x must be 3.<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Ed </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );