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Heights of 50 trees in a nursery are an example of a ____________ variable.

An experiment involves two factors, breed and diet, where there are 3 levels of diet and 4 levels of breed.  This experiment is referred to as a  __________.

Find the variance of a binomial probability distribution with a sample size of n = 40 and a probability of success of 0.40.

For small samples (n < 30), the sampling distribution of the sample mean depends on the particular form of the relative frequency distribution of the population being sampled.

Assume the mean length of time required to complete the Columbus Marathon was 4.5 hours and the standard deviation of the times was 0.70 hours.  Assume that the racing times were approximately normally distrubuted.  Only 10% of the runners would be expected to complete the race in less than x hours.  Find the value of x.

It is desired to estimate the average total compensation of CEO’s in the service industry.  Data were collected from 18 CEO’s and a 97% confidence interval was calculated to be ($2,181,260,  $5,836,180).  Which one of the following interpretations is correct?

Sandoz, a pharmaceutical firm, reports that kidney transplant patients who receive the drug cyclosporine have an 80% chance of surviving the first year.  Suppose a hospital performs 4 kidney transplants and all 4 patients receive cyclosporine.  Assuming that one patient’s survival is independent of another’s, what is the probability that none of the 4 patients will be alive at the end of 1 year?

A scientist conducts an experiment to determine if the mean alkalinity level of water specimens from the Olentangy River is greater than 50 milligrams per liter (mpl).  She selects a random sample of 100 water specimens from the river and finds a sample mean of 67.8 mpl and a sample standard deviation of 14.4 mpl.  She decides to test the hypothesis using a significance level of 0.01.  The critical value used to test this hypothesis is:

The average litter size in Ohio is approximately 8 pigs per litter.  Owners of a particular breed would like to prove that the mean litter size of their breed is greater than 8 pigs per litter.  Therefore, they want to test:      Ho:  μ = 8 pigs/litter      Ha:  μ > 8 pigs/litter They obtain a random sample of 100 litter size records from sows of this breed and find a sample mean of 8.4 pigs per litter and a sample standard deviation of 1 pig per litter.  They decide to use a significance level of α = 0.01. What is the appropriate test statistic needed to test the null hypothesis?

We want to test the hypothesis that the mean number of credit hours taken per semester by OSU undergraduates is less than 16 hours.  Therefore, we obtain a random sample of credit hours for 49 students. The sample mean is 15 hours and the sample standard deviation is 4 hours.  We want to test:    Ho:  μ = 16 hours    Ha:  μ < 16 hours using a significance level (α) = 0.01. What is the calculated value of the test statistic needed to test the null hypothesis in this problem?