document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=174375>Question 174375</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Faced with rising fax costs, a firm issued a guideline that transmission of 10 pages or more<BR>\n" );
document.write( "should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10<BR>\n" );
document.write( "or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard deviation of 4.45 pages. <BR>\n" );
document.write( "(a) At the .01 level of significance, is the true mean greater than 10? NO <BR>\n" );
document.write( "(b) Use Excel to find the right-tail p-value.<BR>\n" );
document.write( "(a) At the .01 level of significance, is the true mean greater than 10? <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #129342 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=129342\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Faced with rising fax costs, a firm issued a guideline that transmission of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. <BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard deviation of 4.45 pages.<BR>\n" );
document.write( "--------------- <BR>\n" );
document.write( "(a) At the .01 level of significance, is the true mean greater than 10? <BR>\n" );
document.write( "Ho: u = 10<BR>\n" );
document.write( "Ha: u > 10<BR>\n" );
document.write( "Critical value for one-tail test with alpha = 1% = 2.32634<BR>\n" );
document.write( "Test statistic: z(14.44) = (14.44-10)/[4.45/sqrt(35)] = 5.9027<BR>\n" );
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document.write( "Conclusion: Since the test statistic is in the \"Reject\" interval,<BR>\n" );
document.write( "reject Ho.  The mean is greater than 10.<BR>\n" );
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document.write( " <BR>\n" );
document.write( "(b) Use Excel to find the right-tail p-value.<BR>\n" );
document.write( "p-value = P(z>5.9027) = 0.00000001793...<BR>\n" );
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document.write( "(a) At the .01 level of significance, is the true mean greater than 10? <BR>\n" );
document.write( "The test provides evidence that the mean is not 10.  Depending on how<BR>\n" );
document.write( "your instructor interprets hypothesis tests, that is all the test shows.<BR>\n" );
document.write( "Some instructors teach that rejecting Ho leads to accepting Ha: but not<BR>\n" );
document.write( "all.<BR>\n" );
document.write( "The test is a test of Ho, not a test of Ha.<BR>\n" );
document.write( "===========<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "</TD></TR></TABLE>\n" );