Question

A special diet is intended to reduce systolic blood pressure among patients diagnosed with stage 2 hypertension. If the diet is effective, the target is to have the average systolic blood pressure of this group be below 150. After six months on the diet, an SRS of 28 patients had an average systolic blood pressure of = 143, with standard deviation s = 21. Is this sufficient evidence that the diet is effective in meeting the target? Assume that the distribution of the systolic blood pressure for patients in this group is approximately Normal with mean μ. The appropriate degrees of freedom for this test are:

a 27

b. 28

c. 20

d. 149.

Answer 1

Solution:

given that,

n = 28

Degrees of freedom is

df = n - 1

= 28 - 1

= 27

Option a is correct.