The lengths of adult males' hands are normally distributed with mean 187 mm and standard deviation is 7.1 mm. Suppose that 12 individuals are randomly chosen. Round all answers to 4 where possible. What is the distribution of ¯ x

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Answer:

By the Central Limit Theorem, the distribution of ¯ x is approximately normal with mean 187 and standard deviation 2.05.

Step-by-step explanation:

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

The lengths of adult males' hands are normally distributed with mean 187 mm and standard deviation is 7.1 mm.

This means that [tex]\mu = 187, \sigma = 7.1[/tex]

Suppose that 12 individuals are randomly chosen.

This means that [tex]n = 12, s = \frac{7.1}{\sqrt{12}} = 2.05[/tex]

What is the distribution of ¯ x?

By the Central Limit Theorem, the distribution of ¯ x is approximately normal with mean 187 and standard deviation 2.05.