A large corporation employs 25,389 individuals. The average income several years ago for all employees was $74,194 with a standard deviation of $19,695. You are interested in comparing the incomes of today's employees with those of several years ago. A random sample of 100 employees of the corporation yields x=$74,586 and s=$18,146. Complete parts a through d below.

a. Describe the center and variability of the population distribution. What shape does it probably have? Explain.

A. It is probably approximately normal because the population size is very large. Populations that are sufficiently large are always approximately normal.

B. It is probably skewed right because the company probably has many lower-level employees with lower incomes and a fewupper-level employees with very high incomes.

C. It is probably uniform because the company probably has many set levels of employee ability where incomes are fixed for a given ability level

D. It is probably skewed left because the company probably has many upper-level employees with very high incomes and a fewlower-level employees with lower incomes

b. Describe the center and variability of the data distribution. What shape does it probably have? Explain.

c. Describe the center and variability of the sampling distribution of the sample mean for

What shape does the sampling distribution have?

It is approximately normal because all sampling distributions with sufficiently large sample sizes are approximately normal.

It is skewed right because the population distribution is probably skewed right.

It is uniform because the population distribution is probably uniform.

It is skewed left because the population distribution is probably skewed left.

d. Explain why it would not be unusual to observe an individual who earns more than $100,000, but it would be highly unusual to observe a sample mean income of more than$100,000 for a random sample size of 100 people.

 

It would not be unusual to observe an individual eaming more than $100,000 because this is well three Vstandard deviations of the mean. It would be highly unusual to observe a sample mean income above $100,000 for a random sample size of 100 people because this is well three Vstandard deviations from the mean