document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1041325>Question 1041325</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You receive a brochure from a large university. The brochure indicates that the mean class size for&#8203; full-time faculty is fewer than 32 students. You want to test this claim. You randomly select 18 classes taught by&#8203; full-time faculty and determine the class size of each. The results are shown in the table below. At a&#945;equals=0.05, can you support the&#8203; university's claim?<BR>\n" );
document.write( "35 28 29 33 32 40 27 26 25 29 28 30 36 33 29 30 28 25<BR>\n" );
document.write( "A. What is the P value? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #656281 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=656281\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "Given Data Set<BR>\n" );
document.write( "{35,28,29,33,32,40,27,26,25,29,28,30,36,33,29,30,28,25}\r<BR>\n" );
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document.write( "Using a calculator, we find that<BR>\n" );
document.write( "sample mean = xbar = 30.16667<BR>\n" );
document.write( "sample standard deviation = s = 4.00367\r<BR>\n" );
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document.write( "Hypothesis<BR>\n" );
document.write( "H0: mu >= 32<BR>\n" );
document.write( "H1: mu < 32<BR>\n" );
document.write( "This is a one-tailed test. Specifically a left-tailed test. \r<BR>\n" );
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document.write( "Test statistic:<BR>\n" );
document.write( "t = (xbar - mu)/(s/sqrt(n))<BR>\n" );
document.write( "t = (30.16667 - 32)/(4.00367/sqrt(18))<BR>\n" );
document.write( "t = -1.9427 5763 2601 19<BR>\n" );
document.write( "t = -1.94\r<BR>\n" );
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document.write( "Now use a TI83 or TI84 calculator to compute the area to left of t = -1.94\r<BR>\n" );
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document.write( "Type in <font color=blue>tcdf(-99,-1.94,17)</font> to get the result 0.0344\r<BR>\n" );
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document.write( "So the p-value is approximately 0.0344\r<BR>\n" );
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document.write( "Side note: because the p value is smaller than alpha = 0.05, this means we reject the null hypothesis and conclude that the mean (mu) is smaller than 32<BR>\n" );
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