Question

In: Statistics and Probability

Identify the distribution of the sample mean. In particular, state whether the distribution of x is...

Identify the distribution of the sample mean. In particular, state whether the distribution of x is normal or approximately normal and give its mean and standard deviation.

10) The weights of people in a certain population are normally distributed with a mean of 152 lb and a standard deviation of 25 lb. Determine the sampling distribution of the mean for samples of size 5.

A) Approximately normal, mean = 152 lb, standard deviation = 11.18 lb

B) Approximately normal, mean = 152 lb, standard deviation = 5 lb

C) Normal, mean = 152 lb, standard deviation = 25 lb

D) Normal, mean = 152 lb, standard deviation = 11.18 lb Provide an appropriate response.

partB) The amount of rainfall in January in a certain city is normally distributed with a mean of 4.1 inches and a standard deviation of 0.4 inches. Find the value of the 25th percentile, rounded to the nearest tenth.

A) 3.8

B) 4.4

C) 3.9

D) 1.0

Use a table or technology to answer the question.

partC) Find the probability that a z-score will be more than .

A) 0.0701

B) 0.0107

C) 0.0487

Expert Solution

The solution is done showing all steps with required formulas. For better understanding a z-table is also attached. Hope you can understand.

z-table -

orchestra answered 1 year ago

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