document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1080764>Question 1080764</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2.	Spiffy Sports has determined that the mean time it takes to process an order placed on its website is 23 minutes with a standard deviation of 8 minutes.  Suppose a random sample of 36 online orders are selected.         2 MARKS\r<BR>\n" );
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document.write( "a.	What is the probability that the mean of the selected sample is less than 20 minutes?  \r<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 #694874 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=694874\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .	Spiffy Sports has determined that the mean time it takes to process an order placed on its website is 23 minutes with a standard deviation of 8 minutes. Suppose a random sample of 36 online orders are selected. 2 MARKS \r<BR>\n" );
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document.write( "a.	What is the probability that the mean of the selected sample is less than 20 minutes? <BR>\n" );
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document.write( "z(20) = (20-23)/(8/sqrt(8)) = -1.06<BR>\n" );
document.write( "P(x-bar < 20) = P(z < -1.06) = normalcdf(-100,-1.06) = 0.1446<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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