document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=260660>Question 260660</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many numbers from 1 to 20 inclusive must be on a blackboard before the probability of two of them being the same is greater than 1/2?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #192023 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=192023\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How many numbers from 1 to 20 inclusive must be on a blackboard before the probability of two of them being the same is greater than 1/2?<BR>\n" );
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document.write( "Assume there are \"x\" numbers on the board.<BR>\n" );
document.write( "You are picking with replacement.<BR>\n" );
document.write( "P(you pick one of the \"x\" numbers on the next draw is x/20)<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "Solve x/20 > 1/2<BR>\n" );
document.write( "x > 10<BR>\n" );
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document.write( "Ans: x = 11<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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