Answer:
Option A is right.
Step-by-step explanation:
Given that a new cream that advertises that it can reduce wrinkles and improve skin was subject to a recent study. A sample of 50 women over the age of 50 used the new cream for 6 months. Of those 50 women, 44 of them reported skin improvement(as judged by a dermatologist)
(Right tailed test)
Sample size = 50
Std error of proportion =
p difference=
Z statistic = p diff/std error = 6.928
p value <0.00001
Since p is less than alpha, reject null hypothesis.
A. We can reject the null hypothesis that p=0.4 and accept that p>0.4. That is, the cream can improve the skin of more than 40% of women over 50.