Essentials of Statistics (5th Edition)

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

Chapter 9 - Inferences from Two Samples - 9-2 Two Proportions - Page 445: 14

Answer

a. The claim is supported. b. The claim is supported. c. The two departments have similar hit rates.

Work Step by Step

a. We want to see if the mean is less than $\frac{182}{540}=.3370$, so we know $H_0: \mu = ..3370$ and $H_1: \mu \ne .3370$. We now use a Ti-84 calculator. To solve, go to "Stat," then "Tests," and then select "Stats." Doing this, we find that the critical value and use a z-table calculator to find that p is less than .05, so the claim is valid. b. We use a ti-84 to find the confidence interval. To do this, we press “Stat” and then select “Tests.” Next, we select “2-PropZInt” to conduct the test. Doing this, we find that the confidence interval goes through 0, so the claim is valid. c. The results show that the two police departments do have the same hit rates.
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.