Answer
a. The claim is supported.
b. The claim is supported.
c. The treatment is effective.
Work Step by Step
a. We want to see if the mean is less than $\frac{29}{148}=.1959$, so we know $H_0: \mu = .1959$ and $H_1: \mu \gt .1959$. We now use a Ti-84 calculator. To solve, go to "Stat," then "Tests," and then select "Stats." Doing this, we find that the critical value and use a z-table calculator to find that p is 0.000, which is less than .05, so the claim is valid.
b. We use a ti-84 to find the confidence interval. To do this, we press “Stat” and then select “Tests.” Next, we select “2-PropZInt” to conduct the test. Doing this, we find that the confidence interval is between .467 and .687. This is greater than 0, meaning that the treatment does improve the patient's well-being.
c. The results show that the treatment works and does, indeed, help treat headaches.
