document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=447602>Question 447602</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a real estate agent believes that the average closing cost of purchasing a new home is $6500 over the purchase price . She selects 40 new home sales at random and finds that the average closing costs are $6600. the standard deviation of the population is $120. Test her belief at a=0.05 <BR>\n" );
document.write( "please help  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #308114 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=308114\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a real estate agent believes that the average closing cost of purchasing a new home is $6500 over the purchase price . She selects 40 new home sales at random and finds that the average closing costs are $6600. the standard deviation of the population is $120. Test her belief at a=0.05 <BR>\n" );
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document.write( "Ho: u = 6500<BR>\n" );
document.write( "Ha: u is not equal to 6500<BR>\n" );
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document.write( "t(6600) = (6600-6500)/[120/sqrt(40)] = 5.2705<BR>\n" );
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document.write( "p-value = 2*P(t > 5.2705 when df = 39) = 0.0000053169..<BR>\n" );
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document.write( "Conclusion: Since the p-value is less than 5%, reject Ho<BR>\n" );
document.write( "at the 5% significance level.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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