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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.  What assumption must be met in order for this confidence interval to be valid?

A college professor wants to estimate the difference in mean test scores of students who have taken his statistics and genetics classes in the past 10 years.  He selects a random sample of 20 student records from the statistics course and a random sample of 22 student records from the genetics course.  These two samples were independent random samples.  The study provided the results shown in the table below.  Calculate the pooled estimate of the variance.   Statistics Genetics Sample size 20 22 Sample mean 78 75 Sample standard dev. 10 12

A random sample of sale prices of homes in Columbus, Ohio yielded the following summary information:      Median = $125,000     Lower quartile = $82,000     Upper quartile = $168,000      Lowest price = $46,000     Highest price = $276,000 Construct a box plot for these data.  Based on this box plot, is the lowest selling price of $46,000 a suspect or highly suspect outlier?

The birth weights of a sample of 8 calves (in pounds) are as follows:   66    70    64    88    74    72    87    79 Calculate the variance of this sample of 8 calf birth weights.

We are interested in determining whether men’s and women’s attitudes concerning the environment are different.  Therefore, we sample 100 men and 100 women and ask:  “Do you think environmental issues are a major concern”?  Of those sampled, 67 women and 53 men responded that they believe environmental issues are a major concern. Perform the calculations needed to determine whther or not it would be appropriate to construct a large-sample confidence interval for (p1 – p2).  Is it appropriate?  Why or why not?

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. What are the correct degrees of freedom?

In a pizza takeout restaurant, the following probability distribution was obtained.  The random variable X represents the number of toppings for a large pizza.                                                                                      x             0          1          2          3          4          P(x)          0.30     0.40     0.20     0.06     0.04          Calculate the mean (µ) of this discrete probability distribution.

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.

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 _______.