document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1119809>Question 1119809</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It is reported that 24% of American households use a cell phone exclusively for their telephone service. In a sample of nine households, find the probability that:\r<BR>\n" );
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document.write( "a.	<BR>\n" );
document.write( "No household uses a cell phone as their exclusive telephone service. (Round your answer to 4 decimal places.)\r<BR>\n" );
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document.write( "  Probability	<BR>\n" );
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document.write( "b.	<BR>\n" );
document.write( "Exactly 6 households exclusively use a cell phone for telephone service. (Round your answer to 4 decimal places<BR>\n" );
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document.write( "c.	<BR>\n" );
document.write( "Find the mean number of households exclusively using cell phones. (Round your answer to 4 decimal places.)\r<BR>\n" );
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document.write( "  Mean	<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 #735430 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=735430\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a. No cell phone for each of 9 is 0.76^9=0.0846<BR>\n" );
document.write( "b. This would be 9C3*0.24^6*0.76^3=0.0070.  The expected value would be 2.16 (.24*9), so this is a reasonable probability.<BR>\n" );
document.write( "c. The expected value above of 2.14 is np, and that is the mean value of houses. </SPAN>\n" );
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