Question 205362
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.
sample proportion: 64/290 = 0.22..
Margin of error: E = 1.96*sqrt[0.22*0.78/290] = 0.047
95% CI: 0.22-0.047 < p < 0.22+0.047
95% CI: (0.173 , 0.268)
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(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?
0.25 in the 95% confidence interval so we would not reject an Ho
which stated p<=0.25
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Show how this confidence interval is equivalent to a two-tailed test at a=.05.
The left and right limits of the confidence interval correspond to the 
critical values for a two-tailed test with alpha = 5%.
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Cheers,
Stan H.
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