Essentials of Statistics (5th Edition)

Published by Pearson
ISBN 10: 0-32192-459-2
ISBN 13: 978-0-32192-459-9

Chapter 7 - Estimates and Sample Sizes - 7-3 Estimating a Population Mean - Page 354: 35

Answer

μ is between 8.156 and 11.46.

Work Step by Step

Given mean:9.808. Given $\sigma$:5.013. $\alpha=1-0.98=0.02.$ $\sigma$ is known, hence we use the z-distribution using the table. $z_{\alpha/2}=z_{0.01}=2.33.$ Margin of error:$z_{\alpha/2}\cdot\frac{\sigma}{\sqrt {n}}=2.33\cdot\frac{5.013}{\sqrt{50}}=1.652.$ Hence the confidence interval:$\mu$ is between 9.808-1.652=8.156 and 9.808+1.652=11.46.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.