document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=457143>Question 457143</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The recovery rate from a flu is 0.9.  If 4 people have this flu, what is the probability that:\r<BR>\n" );
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document.write( "a) all will recover?<BR>\n" );
document.write( "b) at least 2 will recover?<BR>\n" );
document.write( "c) exactly 2 will recover?\r<BR>\n" );
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document.write( "Assume independence.\r<BR>\n" );
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document.write( "Thanks so much for your help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #313659 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=313659\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The recovery rate from a flu is 0.9. If 4 people have this flu, what is the probability that: <BR>\n" );
document.write( "a) all will recover?<BR>\n" );
document.write( "Ans: (0.9)^4 = <BR>\n" );
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document.write( "b) at least 2 will recover?<BR>\n" );
document.write( "Ans: P(2<= x <=4) <BR>\n" );
document.write( "= 1 - P(0<= x <=2) <BR>\n" );
document.write( "= 1-binomcdf(4,0.9,2) <BR>\n" );
document.write( "= 1-0.0523<BR>\n" );
document.write( "= 0.9477<BR>\n" );
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document.write( "c) exactly 2 will recover? <BR>\n" );
document.write( "Ans: P(x = 2) = 4C2(0.9)^2(0.1)^2 = binompdf(4,0.9,2) = 0.048600<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " </SPAN>\n" );
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