document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1013677>Question 1013677</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A proffessor does not remember which of his keys will open his office door . if he tries them at random and with replacement <BR>\n" );
document.write( "a.what is the probability that he opens his office door at the third trial ? <BR>\n" );
document.write( "B.what is the probability that at least 6 trials have to be made to open the office ? <BR>\n" );
document.write( "C. What is the expected value of the trials to open his door ?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #629950 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=629950\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> depends on how many keys he has. </SPAN>\n" );
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