document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=126321>Question 126321</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The following data is a random sample of 1st quiz scores from previous classes.<BR>\n" );
document.write( "9.5, 6.5, 4.25, 8.5, 7.5, 4.5, 4.25, 6, 7<BR>\n" );
document.write( " x=6.44	s = 1.89<BR>\n" );
document.write( "A)	Based on the above data, find a 95% confidence interval for the average score on the 1st quiz.<BR>\n" );
document.write( "B)	Describe what the confidence interval tells you<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #92561 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=92561\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The following data is a random sample of 1st quiz scores from previous classes.<BR>\n" );
document.write( "9.5, 6.5, 4.25, 8.5, 7.5, 4.5, 4.25, 6, 7<BR>\n" );
document.write( "x-bar=6.44 s = 1.89<BR>\n" );
document.write( "A) Based on the above data, find a 95% confidence interval for the average score on the 1st quiz.<BR>\n" );
document.write( "t-value for a two-tailed test with alpha = 5% and 8 degrees of freedom = 2.306<BR>\n" );
document.write( "E = t*(s/sqrt(n))<BR>\n" );
document.write( "E = 2.306*(6.44/sqrt(9))<BR>\n" );
document.write( "E = 1.074224<BR>\n" );
document.write( "95% Confidence Interval: (6.44-1.074224,6.44+1.074224) = (5.3657765 ,7.514224)<BR>\n" );
document.write( "-------------------------------------------------<BR>\n" );
document.write( "B) Describe what the confidence interval tells you<BR>\n" );
document.write( "We are 95% confident that the population mean associated with the <BR>\n" );
document.write( "sample data is between those two numbers.<BR>\n" );
document.write( "========================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );