document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1039845>Question 1039845</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average score of 36 teenage boys playing a computer game was 110,000 with a standard deviation of 20,000. What is the 95% confidence interval for the true mean score of all teenage boys? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #654845 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=654845\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 110000+/-t(0.975,df=35)*20000/sqrt(36)<BR>\n" );
document.write( "t value is 2.03<BR>\n" );
document.write( "95% CI is 110,000+/-2.03(20000)/6=(103,233,116,767)<BR>\n" );
document.write( "The formula is t*s/sqrt(n)<BR>\n" );
document.write( "Look up the t in the table under 35 (n-1) df, and use 0.05 1 tail/0.025 2-tail which is what this is.  The sample size is 36. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );