document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=602100>Question 602100</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 76% of dog owners buy holiday presentes for their dogs.  Suppose n=4 dog owners are randomly selected.  Find the probability that three or more buy their dog holiday presents.  Round to four decimal places </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #380116 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=380116\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First calculate the individual probabilities P(X = 3) and P(X = 4)\r<BR>\n" );
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document.write( "P(X = x) = (n C x)*(p)^(x)*(1-p)^(n-x)\r<BR>\n" );
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document.write( "P(X = 3) = (4 C 3)*(0.76)^(3)*(1-0.76)^(4-3)\r<BR>\n" );
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document.write( "P(X = 3) = (4 C 3)*(0.76)^(3)*(0.24)^(4-3)\r<BR>\n" );
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document.write( "P(X = 3) = (4)*(0.76)^(3)*(0.24)^1\r<BR>\n" );
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document.write( "P(X = 3) = (4)*(0.438976)*(0.24)\r<BR>\n" );
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document.write( "P(X = 3) = 0.42141696\r<BR>\n" );
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document.write( "P(X = x) = (n C x)*(p)^(x)*(1-p)^(n-x)\r<BR>\n" );
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document.write( "P(X = 4) = (4 C 4)*(0.76)^(4)*(1-0.76)^(4-4)\r<BR>\n" );
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document.write( "P(X = 4) = (4 C 4)*(0.76)^(4)*(0.24)^(4-4)\r<BR>\n" );
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document.write( "P(X = 4) = (1)*(0.76)^(4)*(0.24)^0\r<BR>\n" );
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document.write( "P(X = 4) = (1)*(0.33362176)*(1)\r<BR>\n" );
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document.write( "P(X = 4) = 0.33362176\r<BR>\n" );
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document.write( "Then add them up to get your answer\r<BR>\n" );
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document.write( "P(X >= 3) = P(X = 3) + P(X = 4)\r<BR>\n" );
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document.write( "P(X >= 3) = 0.42141696 + 0.33362176\r<BR>\n" );
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document.write( "P(X >= 3) = 0.75503872\r<BR>\n" );
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document.write( "So the probability that three or more buy their dog holiday presents is <font color=\"red\">0.75503872</font>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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