1. Assume the weekly costs for full-time daycare in some large city have a mean of $120, and a standard deviation of $24. Suppose a random sample of 40 daycare facilities is selected. A. Give the properties of the sampling distribution for the sample mean weekly cost. B. What is the probability the sample mean weekly cost will be over $125?

4. The average salary for first-year teachers is $27,989. Assume the distribution is approximately normal with standard deviation $3250. a. What is the probability that a randomly selected first-year teacher makes between $20,000 and $30,000 each year? b. What is the probability that a randomly selected first-year teacher has a salary less than $20,000?

Suppose two graduating seniors, one a marketing major and one an accounting major, are comparing job offers. The accounting major has an offer for $53,000 per year, and the marketing major has an offer for $49,000 per year. Summary information about the distribution of the offers is shown below:   Accounting:  mean:  50000                 standard deviation:  1500 Marketing:  mean:  45500                   standard deviation:  1000   Which offer is more attractive and why?

The distribution of income in some Third World countries is considered very right skewed (many very poor people, very few middle income people, and even fewer wealthy people). Suppose we pick a country with a severely right skewed distribution. Let the average salary be $2,000 per year with a standard deviation of $8,000. We randomly survey 1,000 residents of that country. a. What is the sampling distribution of the sample mean, including name of the distribution, its mean, error, and standard ?

Suppose that the average number of sick days that a person at the company takes per year is 3.2 with a standard deviation of .75. You select a sample of 125 employees. a. Is the sampling distribution for the mean of the sick days for 125 employees normally distributed? Explain how you know in complete sentences and be specific. b. What is the mean and standard deviation for the sampling distribution for the mean of 125 employees sick days? Show your work and calculations. c. Suppose that a group of 125 employees has a mean of 3.7 days. What is the probability that a group of 125 employees would take more sick days than them? You should use technology to find this value and write the probability notation. d. Suppose that a group of 35 employees has a mean of 3.5 days. Would that group have taken an unusual number of sick days?

The distribution of income in some Third World countries is considered very right skewed (many very poor people, very few middle income people, and even fewer wealthy people). Suppose we pick a country with a severely right skewed distribution. Let the average salary be $2,000 per year with a standard deviation of $8,000. We randomly survey 1,000 residents of that country. a. What is the sampling distribution of the sample mean, including name of the distribution, its mean, error, and standard ?

Assume that annual incomes for certain workers are normal, with a mean of $28,500 and standard deviation of $2,400. What is the chance that 36 randomly selected employees earn more than $30,000 on average? Use a sampling distribution of sample means to calculate the standard error.