(1 point) A new cream that advertises that it can reduce wrinkles and improve sk

Question

(1 point) A new cream that advertises that it can reduce wrinkles and improve skin was subject to a recent study. A sample of 52 women over the age of 50 used the new cream for 6 months. Of those 52 women, 41 of them reported skin improvement(as judged by a dermatologist). Is this evidence that the cream will improve the skin of more than 40% of women over the age of 50? Test using = 0.01 . (a) Test statistic: z- (b) Critical Value: Zo - (c) The decision and final conclusion are O A. There is not sufficient evidence to reject the null hypothesis that p s 0.4. That is, we cannot B. We can reject the null hypothesis that p S 0.4 and support the claim that p > 0.4. That is, the cream can improve the skin of more than 40% of women over 50.

Explanation / Answer

The statistical software output for this problem is:

One sample proportion summary hypothesis test:
p : Proportion of successes
H0 : p = 0.4
HA : p > 0.4

Hypothesis test results:

Hence,

a) z = 5.7180

b) z0 = 2.33

c) Option B is correct.

Proportion Count Total Sample Prop. Std. Err. Z-Stat P-value p 41 52 0.78846154 0.067936622 5.717999 <0.0001

Related Questions

Navigate

• Browse (All)
• Browse #
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.