A medical researcher is interested in determining if there is a relationship between blood pressure and regular walk for adults over 50. A random sample of 240 adults over 50 is selected and the results are given below.Test whether the blood pressure is independent of regular walk. (Use = 0.05.)

Blood Pressure	Low	Moderate	High
Walkers	35	64	27
Non-walkers	21	65	28

Figure 1. Blood pressure data.

1. Identify the claim and state the null and alternative hypothesis.
2. Determine the critical value and the rejection region.
3. Calculate the test statistic.
4. Decide whether to reject or fail to reject the null hypothesis. Interpret the decision in the context of the problem.