document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1120130>Question 1120130</A>: <I><SPAN STYLE=\"word-break: break-all;\"> #17<BR>\n" );
document.write( "Suppose that BC financial aid alots a textbook stipend by claiming that the average textbook at BC bookstore costs $ 71.84. You want to test this claim.\r<BR>\n" );
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document.write( "The null and alternative hypothesis in symbols would be:\r<BR>\n" );
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document.write( "    H0:p&#8805;71.84 and H1:p<71.84<BR>\n" );
document.write( "or<BR>\n" );
document.write( "H0:p&#8804;71.84 and H1:p>71.84<BR>\n" );
document.write( "or<BR>\n" );
document.write( "H0:&#956;=71.84 and H1:&#956;&#8800;71.84<BR>\n" );
document.write( "or<BR>\n" );
document.write( "H0:&#956;&#8804;71.84 and H1:&#956;>71.84<BR>\n" );
document.write( "or<BR>\n" );
document.write( "H0:p=71.84 and H1:p&#8800;71.84<BR>\n" );
document.write( "or<BR>\n" );
document.write( "H0:&#956;&#8805;71.84 and H1:&#956;<71.84\r<BR>\n" );
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document.write( "The null hypothesis in words would be:\r<BR>\n" );
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document.write( "    The average of price of all textbooks from the store is less than $\r<BR>\n" );
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document.write( "71.84.<BR>\n" );
document.write( "or <BR>\n" );
document.write( "The average of price of all textbooks from the store is greater than $<BR>\n" );
document.write( "71.84.<BR>\n" );
document.write( "or <BR>\n" );
document.write( "The proportion of all textbooks from the store that are less than 71.84 is equal to 50%<BR>\n" );
document.write( "or<BR>\n" );
document.write( "The average price of all textbooks from the store is $<BR>\n" );
document.write( "71.84<BR>\n" );
document.write( "or<BR>\n" );
document.write( "The average price of textbooks in a sample is $71.84\r<BR>\n" );
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document.write( "Based on a sample of 180 textbooks at the store, you find an average of 80.24 and a standard deviation of 22.6.\r<BR>\n" );
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document.write( "The point estimate is:____ (to 3 decimals)\r<BR>\n" );
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document.write( "The 90 % confidence interval (use z*) is:____ to _____(to 3 decimals)\r<BR>\n" );
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document.write( "Based on this we:\r<BR>\n" );
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document.write( "    Fail to reject the null hypothesis<BR>\n" );
document.write( "  or  Reject the null hypothesis\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #735799 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=735799\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hypothesis statements are always about parameters, not samples<BR>\n" );
document.write( "Ho: mu=$71.84<BR>\n" );
document.write( "Ha: mu NE $71.84\r<BR>\n" );
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document.write( "The point estimate is the sample mean or $80.240<BR>\n" );
document.write( "90% CI has interval t (df=179, 0.95)s/sqrt (n)<BR>\n" );
document.write( "-1.649*22.6/sqrt(180) is interval width or 2.778<BR>\n" );
document.write( "The interval is ($77.462, $83.018)<BR>\n" );
document.write( "Since $71.84 is not in the interval, we reject Ho and conclude the average price is not $71.84<BR>\n" );
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