document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=309463>Question 309463</A>: <I><SPAN STYLE=\"word-break: break-all;\"> There are 8,000 students at the university of Tennessee at Chattanooga. The average age of all the students is 24 years with a standard deviation of 9 years. A random sample of 36 students is selected.<BR>\n" );
document.write( "a. determine the standard error of the mean.<BR>\n" );
document.write( "b. what is the probability that the sample mean will be larger than 19.5?<BR>\n" );
document.write( "c, what us the probability that the sample mean will be between 25.5 and 27 years? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #221340 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=221340\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are 8,000 students at the university of Tennessee at Chattanooga. The average age of all the students is 24 years with a standard deviation of 9 years. A random sample of 36 students is selected.<BR>\n" );
document.write( "a. determine the standard error of the mean.<BR>\n" );
document.write( "Ans: s = 9/sqrt(36) = 3/2<BR>\n" );
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document.write( "b. what is the probability that the sample mean will be larger than 19.5?<BR>\n" );
document.write( "z(19.5) = (19.5-24)/(3/2) = -3<BR>\n" );
document.write( "P(x-bar < 19.5) = P(z < -3) = normalcdf(-100,-3) = 0.0013<BR>\n" );
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document.write( "c, what us the probability that the sample mean will be between 25.5 and 27 years?<BR>\n" );
document.write( "---<BR>\n" );
document.write( "z(27) = (27-24)/(3/2) = 2<BR>\n" );
document.write( "z(25.5) = (25.5-24)/(3/2) = 1<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "P(15.5< x < 27) = P(1< z < 2) = normalcdf(1,2) = 0.1359<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );