Answer
374
Work Step by Step
$\alpha=1-0.99=0.10.$ Then, by using the table, the critical value: $z_{\alpha/2}=z_{0.005}=2.58.$
Hence the sample size:$n=\frac{z^2_{\frac{\alpha}{2}}\cdot \sigma^2}{E^2}=\frac{2.58^2\cdot15^2}{2^2}=374.$
Essentials of Statistics (5th Edition)
by Triola, Mario F.
Published by
Pearson
ISBN 10:
0-32192-459-2
ISBN 13:
978-0-32192-459-9
Chapter 7 - Estimates and Sample Sizes - Review - Chapter Quick Quiz - Page 367: 6
Update this answer!
You can help us out by revising, improving and updating this answer.
Update this answerAfter 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.
