document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=664411>Question 664411</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose the probability that a person has red hair is .15. If 7 people are selected at random, what is the probability that <BR>\n" );
document.write( "a) all 7 have red hair? <BR>\n" );
document.write( "b) at least 1 has red hair?\r<BR>\n" );
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document.write( "show your work. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #413337 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=413337\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P(7 have red hair) = 0.15^7 = 1.71E-6<BR>\n" );
document.write( "P(at least 1 have red hair) = 1 - P(none have red hair)<BR>\n" );
document.write( "P(none) = 0.85^7 = 0.321<BR>\n" );
document.write( "So the probability that at least one has red hair = 1 - 0.321 = 0.679 </SPAN>\n" );
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