document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=234143>Question 234143</A>: <I><SPAN STYLE=\"word-break: break-all;\"> To test the null hypothesis that the average lifetime for a particular brand of bulb is 725 hours versus the alternative that the average lifetime is different from 725 hours, a sample of 90 bulbs is used. If the standard deviation is 75 hours and &#945; is equal to 0.05, what values for  will result in rejection of the null hypothesis (show all work). \r<BR>\n" );
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document.write( "Thanks for all your help!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #172699 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=172699\">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 725 hours versus the alternative that the average lifetime is different from 725 hours, a sample of 90 bulbs is used. <BR>\n" );
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document.write( "If the standard deviation is 75 hours and &#945; is equal to 0.05, what values for will result in rejection of the null hypothesis (show all work). <BR>\n" );
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document.write( "A two-tail test is implied.<BR>\n" );
document.write( "The rejection interval is a function of alpha = 5% and the degrees of freedom.<BR>\n" );
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document.write( "invT(0.025,89) = -1.0987<BR>\n" );
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document.write( "The rejection interval is (-inf,-1.0987)U(1.0987,+inf)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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