Question

Salary information regarding male and female employees of a large company is shown below.

Male Female

Sample Size: 64 36

Sample Mean Salary (in $1,000): 44 41

Population Variance:    128 72

1.) The standard error for the difference between the two means is

2.) The point estimate of the difference between the means of the two populations is

3.) At 95% confidence, the margin of error is

4.)  The 95% confidence interval for the difference between the means of the two populations is

5.) If you are interested in testing whether or not the average salary of males is significantly greater than that of females, the test statistic is

Answer 1

1)

2)

Point estimate of difference

=x1-x2               =

3.000

3)

margin of error E=z*std error                            =

3.920

4) 95% confidence interval for the difference between the means of the two populations is =-0.92 ; 6.92

5)

test stat z                                       =

(x1-x2-Δo)/std error    =

1.50