Question

In: Statistics and Probability

In the United States, according to a 2018 review of National Center for Health Statistics information,...

In the United States, according to a 2018 review of National Center for Health Statistics information, the average age of a mother when her first child is born in the U.S. is 26 years old. A curious student at CBC has a hypothesis that among mothers at community colleges, their average age when their first child was born is lower than the national average. To test her hypothesis, she plans to collect a random sample of CBC students who are mothers and use their average age at first childbirth to determine if the CBC average is less than the national average.

a.) State this study as a formal hypothesis test.

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b.) How would the student make a Type I Error in this study?

The curious student gathers her sample. She ends up with a random sample of 22 mothers at CBC. Among her sample, she finds their average age at first childbirth is 24.4 years old, with a standard deviation of 3.6 years. Help our curious student make a decision at the ?? = 0.05 level.

c.) Calculate the Test-Statistic for the test.

d.) Calculate the Critical Value for the test.

e.) Approximate the p-value.

f.) What is your decision? Be sure to interpret your decision in a way that would make sense to someone that is not a statistician.

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