Question 1133949:  Use the sample data and confidence level given below to complete parts (a) through (d). 
A research institute poll asked respondents if they felt vulnerable to identity theft. In the poll, n equals 1011 and x equals 582 who said "yes." Use a 90 % confidence level.
 
a) Find the best point estimate of the population proportion p. 
(Round to three decimal places as needed.) 
 
b) Identify the value of the margin of error E = 
(Round to three decimal places as needed.)
 
 
c) Construct the confidence interval. 
(Round to three decimal places as needed.)
 
 
d) Write a statement that correctly interprets the confidence interval. Choose the correct answer below. 
A. 
One has 99% confidence that the sample proportion is equal to the population proportion. 
B. 
There is a 99% chance that the true value of the population proportion will fall between the lower bound and the upper bound. 
C. 
One has 99% confidence that the interval from the lower bound to the upper bound actually does contain the true value of the population proportion. 
99% of sample proportions will fall between the lower bound and the upper bound. 
 
 Answer by Boreal(15235)      (Show Source): 
You can  put this solution on YOUR website! x bar is 582/1011=0.576 point estimate 
error is z(0.95)*sqrt(p*(1-p)/n)=1.645*sqrt(0.000242)=0.026 
the 90%CI is (0.550, 0.602) 
One has 99% confidence that the true value of the population mean falls in this interval. A is wrong because it has to do with the parameter, not the statistic.  B uses "chance," not confidence, and is wrong. 
C is correct. 
D, if that is truly D, is not correct.  99% of the confidence intervals constructed will contain the true population interval, but one doesn't know which 99. 
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