Missy Walters Owns a Mail-Order Business Specializing in Baby Clothes

question 66

Essay

Missy Walters owns a mail-order business specializing in baby clothes. Missy is confident the dollar amounts of all her orders are normally distributed or nearly so. Assume she knows the mean and standard deviation are $249 and $46, respectively, for all orders she receives.
a. Describe the sampling distribution of , where is the mean dollar-amount of an order for a sample of 10 orders.
b. What is the probability that a simple random sample of 30 orders will provide an estimate of the population mean dollar-amount of an order that is within plus or minus $10 of the actual population mean?
c. What happens to the sampling distribution of when the sample size is increased from 30 to 90? With a sample size of 90, what is the probability that will be between $239 and $259?

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Definitions:

Estrogen Levels

The concentration of estrogen hormones in the body, which are crucial for the development and regulation of the female reproductive system and secondary sexual characteristics.

Canadian Mental Health Association

A non-profit organization that promotes mental health awareness and supports the recovery of people experiencing mental illness.

Mental Health Disorders

A wide range of conditions that affect mood, thinking, and behavior, requiring clinical diagnosis and management.

Incidence

The frequency or rate at which new cases of a condition, disease, or event occur in a specific population over a certain period.