document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=205362>Question 205362</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780072966930/algebrahomeworkh>Applied Statistics in Business and Economics, by Doane Seward</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A consumer agency tested 290 hams, finding that 64 were underweight. (a) Construct a 95 percent confidence interval for the true percent of underweight hams. (b) If the goal is to reduce the incidencw of underweight hams to 25 percent or less, does this sample show that the goal is being acheived? (c) Explain how this confidence interval is equivalent to a two-tailed test at a=.05. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #155103 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=155103\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A consumer agency tested 290 hams, finding that 64 were underweight. <BR>\n" );
document.write( "(a) Construct a 95 percent confidence interval for the true percent of underweight hams.<BR>\n" );
document.write( "sample proportion: 64/290 = 0.22..<BR>\n" );
document.write( "Margin of error: E = 1.96*sqrt[0.22*0.78/290] = 0.047<BR>\n" );
document.write( "95% CI: 0.22-0.047 < p < 0.22+0.047<BR>\n" );
document.write( "95% CI: (0.173 , 0.268)<BR>\n" );
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document.write( "(b) If the goal is to reduce the incidence of underweight hams to 25 percent or less, does this sample show that the goal is being achieved?<BR>\n" );
document.write( "0.25 in the 95% confidence interval so we would not reject an Ho<BR>\n" );
document.write( "which stated p<=0.25<BR>\n" );
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document.write( "Show how this confidence interval is equivalent to a two-tailed test at a=.05.<BR>\n" );
document.write( "The left and right limits of the confidence interval correspond to the <BR>\n" );
document.write( "critical values for a two-tailed test with alpha = 5%.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " </SPAN>\n" );
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