A new cream that advertises that it can reduce wrinkles and improve skin was subject to a recent study. A sample of 60 women over the age of 50 used the new cream for 6 months. Of those 60 women, 50 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 α=0.05 test statistics z=? rejection region z>? The final conclustion is 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. B. There is not sufficient evidence to reject the null hypothesis that p=0.4 That is, there is not sufficient evidence to reject that the cream can improve the skin of more than 40% of women over 50.

A new cream that advertises that it can reduce wrinkles and improve skin was subject to a recent study. A sample of 60 women over the age of 50 used the new cream for 6 months. Of those 60 women, 50 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 α=0.05 test statistics z=? rejection region z>? The final conclustion is 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. B. There is not sufficient evidence to reject the null hypothesis that p=0.4 That is, there is not sufficient evidence to reject that the cream can improve the skin of more than 40% of women over 50.

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.1: Measures Of Center

Problem 9PPS

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