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The weaning weights (in kilograms) of a sample of 6 lambs born and raised on Farmer Jones’ farm are as follows: Lamb Weight 1 30 2 32 3 28 4 42 5 40 6 44 Find the median weaning weight of this sample of 6 lambs.

The heights in inches of young growing trees were measured at a nursery and used to construct the following stem-and-leaf display using the first digit as the stem and the second digit as the leaf: Stem                       Leaves                                     3               2     4 4               0     3     4     5     7     8     9 5               0     1     2     3     4     5 6               1     2     5     6     7 7               0     1 8 9               8 Construct a box plot for these data.  The correct inner and outer fences for the box plot are _______, _______, _______, and _______.

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. Should we reject or not reject the null hypothesis?  Why?

A randomized block design is used to compare postweaning average daily gains of 4 breeds of beef cattle, Hereford, Angus, Charolais, and Simmental (we can think of the breeds at the “treatments”).  The breeds are divided into 3 weight classes (i.e., 3 blocks).  Block 1 contains cattle weighing 450 to 500 lb at the beginning of the experiment, block 2 contains cattle weighing 500 to 550 lb at the beginning of the experiment, and block 3 contains cattle weighing 550 to 600 lb at the beginning of the experiment.  The postweaning average daily gains (in pounds per day) are as follows:  Block Hereford Angus Charolais Simmental 1 3.50 3.60 3.70 3.75 2 3.55 3.63 3.71 3.80 3 3.56 3.62 3.80 3.90 The partially completed ANOVA table for this experiment is as follows: Source df SS MS F Total   .160     Breed   .139 .046 46 Block   .014 .007   Error   .007 .001   Calculate the F statistic for blocks.

The weights in pounds of 23 dogs were used to construct the following stem-and-leaf display using the first digit as the stem and the second digit as the leaf:. Stem     Leaves                                                    3            2     4 4            0     3     4     5     7     8     9 5            0     1     2     3     4     5 6            1     2     5     6     7 7            0     1 8 9            8 Use the stem-and-leaf display to find the lower quartile, median, and upper quartile and then use these values to construct a box plot.  The correct values for the lower outer fence, lower inner fence, upper inner fence, and upper outer fence are ______, ______, ______, and ______ lb, respectively.

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 Total Sums of Squares.

Assume X is a binomial random variable.  If n = 20 and p = 0.20, find P (r = 2 successes).

A random sample of 16 Standardbred horses was selected from a population of Standardbreds.  The mean time required for these 16 horses to run a mile while pulling a sulky was 130 seconds (i.e., 2 minutes and 10 seconds),  The standard deviation of the sample was 10 seconds. What is the point estimate of the true population mean for racing time of Standardbred horses?

A vet clinic has found that the number of patients per day has an average of 100 and a standard deviation of 10.  If nothing is known about the shape of the distribution of number of patients seen per day, what percentage of the days would be expected to have between 70 and 130 patients?

A 2 x 4 factorial experiment is conducted to compare yields of 4 varieties of soybeans that are planted in rows either 15 inches or 30 inches apart.  Two plots of ground are randomly assigned to each combination of soybean variety and row spacing.  The yields of soybeans (in bushels per acre) are as follows:           Rows 1 2 3 4 15″ 45 46 47 46   46 46 48 43 30″ 35 41 42 39   32 39 38 41 The partially completed ANOVA table is as follows: Source df SS MS F Total   319.75     Variety   41.25 13.75 5.0 Row spacing   225 225 81.8 Variety x row spacing   31.5     Error   22 2.75   Calculate the mean squares and then the F value for the variety x row spacing interaction.