document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=206540>Question 206540</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Backyard Retreats, Inc, sells an exclusive line of pools, hot tubs, and spas. It is located just off the Bee Line Expressway in Orlando, Florida. The owner reports 20% of the customers entering the store will make a purchase of at least $50. Suppose 15 customers enter the store before 10am on a particular Saturday <BR>\n" );
document.write( "a) How many of these customers would you expect to make a purchase of at least $50?<BR>\n" );
document.write( "b) What is the probability exactly five of these customers make a purchase of at least $50?<BR>\n" );
document.write( "c) What is the probability at least five of these customers make a purchase of at least $50?<BR>\n" );
document.write( "d) What is the probability at least one customers make a purchase of at least $50?<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 #156080 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=156080\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The owner reports 20% of the customers entering the store will make a purchase of at least $50. Suppose 15 customers enter the store before 10am on a particular Saturday <BR>\n" );
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document.write( "The problem is binomial with p = 0.2, and n= 15<BR>\n" );
document.write( "a) How many of these customers would you expect to make a purchase of at least $50?<BR>\n" );
document.write( "mean = np = 15*0.2 = 3<BR>\n" );
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document.write( "b) What is the probability exactly five of these customers make a purchase of at least $50?<BR>\n" );
document.write( "P(x+5) = 15C5(0.2)^5(0.8)10 = 0.1032<BR>\n" );
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document.write( "c) What is the probability at least five of these customers make a purchase of at least $50?<BR>\n" );
document.write( "P(5<=x<=15) = 1-binomcdf(15,0.2,4) = 0.1642<BR>\n" );
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document.write( "d) What is the probability at least one customers make a purchase of at least $50?<BR>\n" );
document.write( "P(at least one) = 1 - P(none)<BR>\n" );
document.write( "= 1 - binompdf(15,0.2,0) = 0.9648<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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