document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1193651>Question 1193651</A>: <I><SPAN STYLE=\"word-break: break-all;\"> According to the norms established for a history test,grade 8 students should have an average 81.7 with a standard deviation of 8.5.If 100 randomly selected grade 8 students from certain school district average 79.6 in this test,can we conclude at the 0.05 level of significance that grade 8 students from this school district can be expected to average less than the norm of 81.7? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #825688 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=825688\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ho: mean is 81.7 or higher<BR>\n" );
document.write( "Ha: mean is <81.7<BR>\n" );
document.write( "alpha=0.05 p{reject Ho|Ho true}<BR>\n" );
document.write( "test is a z (0.95)<BR>\n" );
document.write( "critical value is z<-1.645<BR>\n" );
document.write( "calculation z=diff in mean/SE=-2.1/8.5/sqrt(100)<BR>\n" );
document.write( "=-21/8.5=-2.47<BR>\n" );
document.write( "reject Ho: there is a significant difference at the 5% level and the population should be considered to have an average less than 81.7<BR>\n" );
document.write( "p-value =  0.007, well < 0.05.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );