Use the confidence level and sample data to find a confidence interval for estimating the population µ.
-The duration of telephone calls directed by a local telephone company: $\sigma = 4.1$ minutes, $\mathrm { n } = 540$, 97 percent confidence.
A)0.008 minutes
B)0.016 minutes
C)0.081 minutes
D)0.383 minutes

Question

Quizplus · Accepted Answer

The confidence interval is calculated using the formula: $\bar{x} \pm Z \times \frac{\sigma}{\sqrt{n}}$. For a 97% confidence level, the Z-score is approximately 2.17. Plugging in the values: $2.17 \times \frac{4.1}{\sqrt{540}} \approx 0.383$ minutes.

Use the Confidence Level and Sample Data to Find a Confidence