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It seems reasonable to assume that the number of times a team punts the ball in a football game would be negatively correlated with the number of points that the team scores (i.e., if a team is forced to punt frequently they are probably not moving the ball very well and probably are not scoring many points).  Number of punts (variable X) and number of points scored (variable Y) for a particular team in a random sample of five games are as follows: Number of Punts, X          Number of Points, Y              2                                         35              5                                         14              3                                         21              2                                         21              2                                         28   Calculate the variance of variable X (number of punts in a football game).

A population of cats has a mean weight of 15 lb and a standard deviation of the weights equal to 4 lb.  A cat breeder selects a large number of samples of 64 cats each, calculates the mean weight of the cats in each of these samples, and then graphs the sample means. The standard deviation of these sample means is expected to be equal to _______.

Health care issues are receiving a great deal of attention in both the academic and political arenas.  A sociologist recently conducted a survey of citizens over 60 years of age whose net worth is too high to qualify for Medicaid, but who have no private health insurance.  The mean age of the 50 uninsured senior citizens in the survey was 74.04 years and the standard deviation of their ages was 9.75 years.  If we assume that the distribution of ages is symmetric and mound-shaped, what percentage of the respondents in the survey would be expected to be between 64.29 and 83.79 years old?

The sample mean and sample standard deviation are examples of parameters.

A randomized block design was used to compare the mean responses for three treatments.  Four blocks of three homogeneous experimental units were selected, and each treatment was randomly assigned to one experimental unit within each block.  The partially completed ANOVA table for this experiment is as follows: Source               df        SS             MS          F   Total                  11       84.489 Treatments         2       12.032       6.016 Blocks                3       71.749      23.916 Error                  6         0.708        0.118             Do the data provide sufficient evidence to indicate that blocking was effective in reducing variation in the responses?  Use α = 0.05.

An animal scientist is interested in determining the proportion of ewes that give birth to twins.  Rather than examine the records for all ewes in the United States, he randomly selects 500 ewes and finds that 220 of them gave birth to twins.  The animal scientist knows that the sample size of n = 500 is large enough for large-sample confidence interval procedures to be valid, because:

Suppose that 20% of the Golden Retrievers in the U.S. have a particular genetic defect.  We randomly select 4 Golden Retrievers from the population consisting of all Golden Retrievers in the U.S.  What is the probability that exactly 1 of the 4 dogs in this sample will have the genetic defect?  To find the answer to this question, you will need to use the equation for the binomial distribution.

A two-factor factorial experiment is conducted to compare fleece weights of Merino, Suffolk, and Dorset ewes fed one of two diets.  Two ewes of each breed are randomly assigned to each diet.  The fleece weights (in pounds) are as follows:                Merino            Suffolk            Dorset        Diet 1          14                   9                    8                     15                 10                    8 Diet 2           13                   8                  11                     12                    9                 12                                                                                   The partially completed ANOVA table is as follows: Source             df           SS             MS           F      Total                          66.2500 Diet                             0.0833       0.0833       0.19992 Breed                        46.5000     23.2500     55.79955 Diet x Breed              17.1667     Error                            2.5000      0.41667                                                                                       Should we test the hypotheses involving differences in mean levels of the main effects of diet and breed?  Assume that we use a significance level of 0.05.

We have three independent events (A, B, and C) where    P(A) = 0.20     P(B) = 0.30     P(C) = 0.40 Find the probability of all three events occurring at the same time.

The following is a valid probability distribution for a discrete random variable, X: X             0           1            2            3        P (X)     0.20       0.30       0.30       0.20