In testing the difference between two population means using two independent samples,the population standard deviations are assumed to be unknown,each sample size is ? 30,and the calculated test statistic z = 2.56.If the test is two-tail and 5% level of significance has been specified,the conclusion should be to:
A) reject the null hypothesis.
B) not to reject the null hypothesis.
C) choose two other independent samples.
D) none of these answers is correct.

Question

Quizplus · Accepted Answer

Since the calculated test statistic z is greater than the critical value of 1.96 (for a two-tail test at 5% level of significance), we reject the null hypothesis. Thus, the conclusion is that there is a significant difference between the means of two populations.

In Testing the Difference Between Two Population Means Using Two