Independent random samples were selected from two quantitative populations, with sample sizes, means, and variances given below. Population
1 2
Sample Size 32 45
Sample Mean. 9.8 7.3
Sample Variance 10.83 16.49
State the null and alternative hypotheses used to test for a difference in the two population means.
- H0: (1 − 2) = 0 versus Ha: (1 − 2) < 0
- H0: (1 − 2) ≠ 0 versus Ha: (1 − 2) = 0
- H0: (1 − 2) < 0 versus Ha: (1 − 2) > 0
- H0: (1 − 2) = 0 versus Ha: (1 − 2) > 0
- H0: (1 − 2) = 0 versus Ha: (1 − 2) ≠ 0
Calculate the necessary test statistic. (Round your answer to two decimal places.)
z =
Calculate the rejection region with
= 0.01.
(Round your answers to two decimal places. If the test is one-tailed, enter NONE for the unused region.)
z >
z <
Draw the appropriate conclusion.
- H0 is rejected. There is insufficient evidence to indicate a difference in mean.
- H0 is not rejected. There is sufficient evidence to indicate a difference in mean.
- H0 is not rejected. There is insufficient evidence to indicate a difference in mean.
- H0 is rejected. There is sufficient evidence to indicate a difference in mean.