document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=363614>Question 363614</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, \r<BR>\n" );
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document.write( "Cards are drawn at random and with replacement from an ordinary deck of 52 cards until a spade appears. \r<BR>\n" );
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document.write( "What is the probability that at least 4 draws are necessary?\r<BR>\n" );
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document.write( "Thanks!\r<BR>\n" );
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document.write( "Regards,<BR>\n" );
document.write( "Anita </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #259290 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=259290\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .75^3=.4219 probability of all non spades on 3 consecutive draws with replacement.<BR>\n" );
document.write( "1-.4219=.5781 the probability that at least 4 draws are necessary ie. 3 were not enough.<BR>\n" );
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document.write( "Ed </SPAN>\n" );
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