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A poll finds that 64​% of the people surveyed approve of the​ President's handling of the​ economy, with a margin of error​ (for 95%​ confidence) of 3​%. Find the​ 95% confidence interval for this poll.

User JeyJ
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Answer: The 95% confidence interval for this poll is [0.61, 0.67].

Step-by-step explanation: A confidence interval is a range of values that is likely to contain the true population parameter with a certain level of confidence. In this case, we are interested in estimating the proportion of people who approve of the President’s handling of the economy based on a sample of people surveyed. The margin of error for this poll is 3%, which means that we can be 95% confident that the true proportion of people who approve of the President’s handling of the economy falls within the range [0.64 - 0.03, 0.64 + 0.03] = [0.61, 0.67].

The formula for calculating a confidence interval for a proportion is:

p ± z*sqrt(p*(1-p)/n)

where p is the sample proportion, z is the z-score corresponding to the desired level of confidence (in this case, 95%), and n is the sample size.

In this case, p = 0.64, z = 1.96 (corresponding to a 95% confidence level), and n is not given in the question.

Hope this helps, and have a great day!

User Theicfire
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