document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=654342>Question 654342</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Past experience indicates that 30% of all individuals entering a certain store decide to make a purchase. Using a) the binomial distribution and b) the normal approximation to the binomial, find the probability that 10 or more of the 30 individuals entering the store in a given hour will decide to make a purchase. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #408813 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=408813\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Past experience indicates that 30% of all individuals entering a certain store decide to make a purchase. Using a) the binomial distribution and <BR>\n" );
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document.write( "a. P(10<= x <=30) = 1 - P(30,0.30,9) = 0.4112<BR>\n" );
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document.write( "b) the normal approximation to the binomial, find the probability that 10 or more of the 30 individuals entering the store in a given hour will decide to make a purchase.<BR>\n" );
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document.write( "b.mean = np = 0.3*30 = 9<BR>\n" );
document.write( "std = sqrt(npq) = sqrt(9*0.7) = 2.510<BR>\n" );
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document.write( "P(10<= x <=30) = P(9.5<= x <- 30.5)<BR>\n" );
document.write( "z(9.5) = (9.5-9)/2.510 = 0.1992<BR>\n" );
document.write( "z(30.5) = (30.5-9)/2.51 = 8.57<BR>\n" );
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document.write( "P(0.1992<= z <= 8.57) = 0.4211<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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