Question

A pharmaceutical company is testing the effectiveness of a new drug for lowering cholesterol. As part of this trial, they wish to determine whether there is a difference between the effectiveness for women and men. At = 0.05, what is an appropriate test value? Women Men Sample size 50 70 Mean effectiveness 4.9 4 Population variance 2.6 4.6

A. 7.65

B. 0.34

C. 0.38

D. 2.62

Answer 1

using excel>Addin>phstat>two sample test we have

Z Test for Differences in Two Means
Data
Hypothesized Difference	0
Level of Significance	0.05
Population 1 Sample
Sample Size	50
Sample Mean	4.9
Population Standard Deviation	1.612452
Population 2 Sample
Sample Size	70
Sample Mean	4
Population Standard Deviation	2.144761
Intermediate Calculations
Difference in Sample Means	0.9
Standard Error of the Difference in Means	0.343095
Z-Test Statistic	2.623179
Two-Tail Test
Lower Critical Value	-1.95996
Upper Critical Value	1.959964
p-Value	0.008711
Reject the null hypothesis

the value of test stat is 2.62

option D is true