document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=266471>Question 266471</A>: <I><SPAN STYLE=\"word-break: break-all;\"> To test the null hypothesis that the average lifetime for a particular brand of bulb is 750 hours versus the alternative that the average lifetime is different from 750 hours, a sample of 75 bulbs is used. If the standard deviation is 50 hours and a  is equal to 0.01, what values for  will result in rejection of the null hypothesis. Remember to determine whether this is a one- or two-tailed test. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #195813 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=195813\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> To test the null hypothesis that the average lifetime for a particular brand of bulb is 750 hours versus the alternative that the average lifetime is different from 750 hours, a sample of 75 bulbs is used. <BR>\n" );
document.write( "If the standard deviation is 50 hours and a is equal to 0.01, what values for will result in rejection of the null hypothesis. Remember to determine whether this is a one- or two-tailed test.<BR>\n" );
document.write( "=========<BR>\n" );
document.write( "An \"unequal\" test is two tail.<BR>\n" );
document.write( "A \"less than\" test is left-tail.<BR>\n" );
document.write( "A \"greater than\" is right-tail.<BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "Your Problem:<BR>\n" );
document.write( "Ho: u = 750<BR>\n" );
document.write( "Ha: u is not equal to 750<BR>\n" );
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document.write( "critical values = ?<BR>\n" );
document.write( "Find the t-values with 0.005 tails with df = 74<BR>\n" );
document.write( "invT(0.005,74) = -2.6439<BR>\n" );
document.write( "The CV's are -2.6439 and +2.6439<BR>\n" );
document.write( "---<BR>\n" );
document.write( "The rejection intervals are t< -2.6439 and t> 2.6439<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );