document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1171909>Question 1171909</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this equation. It is Hypothesis testing. The question is as follows: The Nero Match Company sells matchboxes that are supposed to have an average of 45 matches per box, with 𝜎 = 12. A random sample of 94 Nero matchboxes shows the average number of matches per box to be 42.1. Using a 5% level of significance, can you say that the average number of matches per box is different from 45? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #796855 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=796855\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ho: M=45<BR>\n" );
document.write( "Ha: M NE 45<BR>\n" );
document.write( "alpha=0.05 P{reject Ho|Ho true}<BR>\n" );
document.write( "test is a z<BR>\n" );
document.write( "critical value |z| >1.96<BR>\n" );
document.write( "calculation z=(x bar-mean/sigma/sqrt(n)<BR>\n" );
document.write( "z=-2.9*sqrt(94)/12<BR>\n" );
document.write( "=-2.34<BR>\n" );
document.write( "this is outside the range of Ho (less than -1.96)<BR>\n" );
document.write( "reject Ho--we conclude the average number of matches per box is not 45 but fewer.<BR>\n" );
document.write( "p-value is 0.019. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );