document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=583477>Question 583477</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine the probability that in a class 23 students, two or more students have birthday on 1 january?<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 #372661 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=372661\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We know that the famous birthday problem states that for a group of 23 people, there is a ~50% chance that two of them have the same birthday. However we can't say that the probability that two of them have a birthday on 1 January is 50%.\r<BR>\n" );
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document.write( "One way to approach this is to say that the probability of any one student having a birthday on 1 January is 1/365 (ignoring leap years). We want two or more students, so the probability is given by\r<BR>\n" );
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document.write( "binomcdf(23, 1/365, 2, 23)\r<BR>\n" );
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document.write( "=0.00183 </SPAN>\n" );
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