The Basic Practice of Statistics 7th Edition

Published by W. H. Freeman
ISBN 10: 146414253X
ISBN 13: 978-1-46414-253-6

Chapter 20 - Inference about a Population Mean - Chapter 20 Exercises - Page 478: 20.29a

Answer

See below.

Work Step by Step

The sample is large (at least $30$), thus the Central Limit Theorem implies that the sampling distribution of the sampling mean is approximately normal. Thus the sample is random, thus we can use the $t$ procedures.
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.