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A magazine provided results from a poll of 2000 adults who were asked to identify their favorite pie. Among the 2000 respondents, 14% chose chocolate pie, and the margin of error was given as ±3 percentage points. Given specific sample data, which confidence interval is wider: the 99% confidence interval or the 80% confidence interval? Why is it wider?

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Answer:

99%

Step-by-step explanation:

We were given specific information:

Population = 2,000 respondents

14% chose chocolate

Margin of error = ±3%

We are to determine which confidence interval is wider between the 80% and 99%. This is answered below:

The formula for confidence interval given this specific information is given by:


CI=P\pm z\sqrt{(pq)/(n)}

This means that the confidence interval is directly proportional to the width i.e. as the interval increases, the width also increases and as the interval decreases, the width also decreases

Therefore, we can thus conclude that the 99% interval has more width than the 80% interval

User John Naegle
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