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The average weight of a kennel of dogs is 40 lb and the standard deviation of the weights is 5 lb.  Find the probability that a randomly selected dog will weigh more than 48 lb.

A Gallop poll is conducted to estimate the proportion of voters who plan to vote in favor of a certain issuse on the ballet.  A random sample of 500 people of voting age is selected.  Results of the poll show that 300 of the 500 people polled plan to vote in favor of the issue.  Perform the calculations needed to determine whether or not it would be appropriate to construct a large-sample confidence interval for the true population proportion.  What do you conclude (i.e., is it appropriate?

A national organization has been working with electric companies throughout the US to find sites for large windmills to generate electric power.  Wind speeds must average more than 21 miles per hour (mph) for a site to be acceptable.  Recently, the organization conducted tests at a particular site where windmills are under construction.  Based on a sample of n = 40 wind speed recordings (taken at random intervals) at the site, the wind speeds averaged 23 mph with a standard deviation of 3.9 mph.  To determine whether the site meets the organization’s requirements, they want to test:    Ho:  μ = 21 mph    Ha:  μ > 21 mph using a significance level (α) = 0.01. Calculate the value of the test statistic needed to test the null hypothesis.

Independent random samples of litter sizes were selected from the Yorkshire and Landrace breeds of swine with the following results: Yorkshire          Landrace 8 pigs                    7 pigs 9                            8 10                          9 8                            8 9                            7 10                               54                        39  The correction factor (correction for the mean) in this problem is 786.27272. Calculate the Error Sums of Squares.

An Animal Scientist wants to estimate the average weaning weight of the Angus breed of beef cattle.  Therefore, he selects a random sample of 100 Angus calves and weighs them on the day they are weaned from their mothers.  The sample mean for these 100 calves is 500 lb and the sample standard deviation is 40 lb.  Which one of the following is the correct 90% confidence interval used to estimate the population mean for the weaning weights of the Angus calves?

A random sample of 4,000 U.S. citizens was asked their opinion concerning gun control.  A total of 2,600 of the 4,000 citizens in the sample stated that they are in favor of gun control legislation.  Perform the calculations needed to determine whether or not it would be appropriate to construct a large-sample confidence interval for the true population proportion (p).  What do you conclude (i.e., is it appropriate) and why?

We want to test the following null and alternative hypotheses about a population proportion: Ho:  p = 0.20 Ha:  p ≠ 0.20 We observe 300 successes in a sample of 1,000 observations.  Assume that it is valid to use large-sample procedures in this problem. Calculate the test statistic needed to test the null hypothesis.

The average height cows of a certain breed is 54 inches and the standard deviation of the heights is 8 inches.  Fifteen percent of the cows are expected to be less than X inches tall.  Find the value of X.

The weights of 25 lambs (in pounds) in a flock of sheep are as follows: 68     73     66     76     86     74     61     89     65     90 69     92     76     62     81     63     68     81     70     73     60     87     75     64     82 Construct a stem-and-leaf display using the first digit as the stem and the second digit as the leaf.  Based on the stem-and-leaf display, the median for this set of weights is __________ lb.

The following table shows litter sizes for sows in four breeds of pigs. Yorkshire     Landrace     Hampshire     Duroc      8                   9                   8                 7     10                  9                   7                 8     11                10                   8                 9     11                10                   9                 7       9                  8                                                 49                46                 32               31 – treatment totals     9.8               9.2               8.0              7.5 – sample means     The correct degrees of freedom for total, treatments, and error in the Analysis of Variance table for this problem are ____________.