document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=233872>Question 233872</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average flight from point A to B takes 40 minutes with a standard deviation of 5 minutes. What is the probability a random sample of 4 flights will take between 38 and 43 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 #172533 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=172533\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The average flight from point A to B takes 40 minutes with a standard deviation of 5 minutes. What is the probability a random sample of 4 flights will take between 38 and 43 minutes? <BR>\n" );
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document.write( "z(38) = (38-40)/[5/[sqrt(4)] = -0.8<BR>\n" );
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document.write( "z(43) = (43-40)/[5/sqrt(4)] = 1.2<BR>\n" );
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document.write( "P(38 < x < 43) = P(-0.8 < z < 1.2) = 0.6731<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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