Answer
See below.
Work Step by Step
$t=\frac{\overline{x_1}-\overline{x_2}}{\sqrt{s_1^2/n_1+s_2^2/n_2}}=\frac{2.91-3.29}{\sqrt{0.139^2/20+0.24^2/19}}\approx-95.07$. $t$ has a very large absolute value, thus it supports the suspicion.
The Basic Practice of Statistics 7th Edition
by Moore, David S.; Notz, William I.; Fligner, Michael A.
Published by
W. H. Freeman
ISBN 10:
146414253X
ISBN 13:
978-1-46414-253-6
Chapter 21 - Comparing Two Means - Apply Your Knowledge - Page 499: 21.10b
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.
