SOLUTION: In a poll of 125 randomly selected U.S. adults, 65 said they favored a new proposition. Based on this poll, compute a 95% confidence interval for the proportion of all U.S. adults

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Question 1159648: In a poll of 125 randomly selected U.S. adults, 65 said they favored a new proposition. Based on this poll, compute a 95% confidence interval for the proportion of all U.S. adults in favor of the proposition (at the time of the poll).
Carry your intermediate computations to at least three decimal places. Round your answers to two decimal places.
What is the lower limit of the 95% confidence interval?

What is the upper limit of the 95% confidence interval?
Answer by Shin123(626) About Me  (Show Source):
You can put this solution on YOUR website!
The Z value for a 95% confidence interval is 1.960. The standard error is sqrt%2865%2A60%2F125%5E3%29, which is 0.045 rounded to three decimal places. The true proportion of all U.S. adults in favor of the proposition is 0.52+/-(1.960*0.045),which is 0.520+/-0.088. The lower bound is highlight%280.432%29 and the upper bound is highlight%280.608%29. Click here for a calculator if you have more problems like this.