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Chapter 8: Q. 25 (page 478)

The mean age for all Foothill College students for a recent Fall term was 33.2. The population standard deviation has been pretty consistent at 15. Suppose that twenty-five Winter students were randomly selected. The mean age for the sample was 30.4. We are interested in the true mean age for Winter Foothill College students. Let X=the age of a Winter Foothill College student.

___=15.

Short Answer

Expert verified

Standard Deviation蟽=15.

Step by step solution

01

Given Information

The mean age for all Foothill College students for a recent Fall term was 33.2. The population standard deviation has been pretty consistent at 15. The mean age for the sample was 30.4.

02

Explanation

The square root of the variance of a set of integers is used to calculate the population standard deviation. It's used to calculate a confidence interval before making a decision (such as accepting or rejecting a hypothesis).

The average of the data set is the mean.

The population standard deviation of the age of the whole Foothill College students for a recent Fall term is 15.

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