Calculate the test statistic for the test for equality of two means.
In testing the equality of the two means below, what is the test statistic? (Make use of the unequal variances formula)
|
Sample 1
|
Sample 2
|
Sample size
|
9
|
12
|
Sample mean
|
80
|
115
|
Sample variance
|
550
|
100
|
a.-4.20
b.-2.31
c.-0.18
d.-0.50