A farmer weighs his pigs before sending them to market.  The herd average market weight is 250 lb and the standard deviation of the weaning weights is 50 lb.  What is the z-score for a pig that weighs 200 lb?

Assume that the mean weight of a sample of calves is 600 lb and the standard deviation of the weights is 50 lb.  If the data set does not have a symmetric and mound shaped distribution, and we therefore use Chebyshev’s Rule, we would expect at least what percent of the calves to have weights between 500 and 700 lb?

You are interested in purchasing a new car.  One of the many points you wish to consider is the resale value of the car after 5 years of ownership.  Since you are particulary interested in a certain foreign sedan, you decide to estimate the resale value of this car with a 95% confidence interval.  You manage to obtain data on 16 recently resold 5-year-old foreign sedans of that model.  These 16 cars were resold at an average price of $10,000 with a standard deviation of $1,000. Estimate the true mean resale value of this model of foreign car using a 95% confidence interval.

Independent random samples of litter sizes were selected from the Yorkshire and Landrace breeds of swine, with the following results: Yorkshire Landrace 8 7 9 8 10 9 8 8 9 7 10   We want to analyze these data using Analysis of Variance with a Completely Randomized Design. Which one of the following statements is true?

The mean length of time required to complete the Columbus Marathon was 4.5 hours.  The standard deviation of the times was 0.50 hours.  Assume that the racing times were approximately normally distributed.  What proportion of the runners would be expected to require between 5.0 and 5.5 hours to complete the race?

The weights (in pounds) of 17 pigs are used to construct the following stem-and-leaf display (the first two digits were used as the stem and the last digit was used as the leaf): Stem                   Leaf                                       16          0     5 17          — 18          — 19          — 20          — 21          — 22          2     4     6 23          0     9 24          0     1     2     3     4     5     9 25          3 26          — 27          — 28          0     5   Based on this stem-and-leaf display, the lower quartile is equal to __________ lb.

Psychologists at the University of Minnesota compared the scores of independent random samples of male and female 8th grade students who took a basic skills math achievement test to determine if males outperform females in math.  A summary of the test score data is shown below:                                            Males          Females     Sample size                         1,764            1,739 Sample means                      48.9              48.4 Sample standard deviations  12.96          11.85                                                                                  Use a 90% confidence interval to estimate the true difference in mean test scores between males and females.

An industrial psychologist is investigating the effects of work environment on employee attitudes.  A group of 20 recently hired sales trainees were randomly assigned to one of 4 different “home rooms” with 5 trainees per room.  Each room was identical except for the color of the walls.  The 4 colors used were light green, light blue, gray, and red.  Therefore, in this experiment the 4 treatments were the 4 room colors.  The psychologist wants to compare the mean attitudes of the trainees assigned to the 4 rooms with different colors.  At the end of the training program, the attitude of each trainee was measured on a 60 point scale (the lower the score, the poorer the attitude).  The data were subjected to an analysis of variance.  The partially completed Analysis of Variance (ANOVA) table was as follows: Source           df       SS              MS              F     Total                       1,829.75 Treatments             1,678.15 Error                          151.60                                      What are the total degrees of freedom, treatment degrees of freedom, and error degrees of freedom?

The Kimberly Clark Corporation wants to determine how many tissues a box of Kleenex should contain.  Researchers determine that 60 is the average number of tissues used by a typical person during a cold.  Suppose a random sample of 100 Kleenex users yielded a sample mean of 56 tissues and a sample standard deviation of 10 tissues used during a typical cold.  Kimberly Clark wants to test:    Ho:  μ = 60 tissues    Ha:  μ < 60 tissues using a significance level (α) = 0.05. What is the correct critical value that should be used to test the null hypothesis?

The average height of a herd of cows is 50 inches and the standard deviation of the heights is 5 inches.  Find the probability that a randomly selected cow will have a height of more than 62 inches.