document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=682803>Question 682803</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A final exam in Statistics has a mean of 73 with a standard deviation of 7.73.  Assume that a random sample of 24 students is selected and the mean test score of the sample is computed. What percentage of sample means are less than 70?   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #423365 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=423365\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A final exam in Statistics has a mean of 73 with a standard deviation of 7.73. Assume that a random sample of 24 students is selected and the mean test score of the sample is computed. What percentage of sample means are less than 70?<BR>\n" );
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document.write( "std of the sample means for samples of size 2 is 7.73/sqrt(24) <BR>\n" );
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document.write( "z(70) = (70-73)/[7.73/sqrt(24)] = 1.9013<BR>\n" );
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document.write( "P(x < 70) = P(z < 1.9013) = normalcdf(-100,1.9013) = 0.9714<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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