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We want to use a confidence interval to estimate the proportion of students in the College of Food, Agricultural, and Environmental Sciences that are female.  What sample size would be necessary if we want to estimate the true proportion of female students correct to within 0.03 with probability 0.95?  In an earlier small-scale pilot study, we obtained an estimate of the proportion of female students (p) that was equal to 0.48.

The symbol for the variance of a population is _______.

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.  List any suspect or highly suspect outliers for this dataset.

The Animal Sciences Department wants to estimate the average length of time it takes students to complete a class project correct to within 5 hours with a 98% level of confidence.  Determine the sample size needed to estimate the average length of time required to complete the project to within 5 hours with a 98% level of confidence if the standard deviation of the times is 4 hours.

Suppose x has a binomial probability distribution with n = 400 and p = 0.70.  Which one of the following statements is correct?

Suppose that a veterinarian has received permission from the owners of 50 dogs to use their dogs in an experiment involving a new drug for cancer treatment.  The vet decides to use 5 of the 50 available dogs for a small preliminary experiment before conducting a larger study.  The vet arbitrarily begins at row 8 column 1 of the random number table and goes from left to right across the row.  Which one of the following is the correct random sample of 5 dogs? For your convenience, here are rows 8 and 9 of the random number table:       Column       Row 1 2 3 4 5 6 8 96301 91977 05463 07972 18876 20922 9 89579 14342 63661 10281 17453 18103

Parking at a large university has become a big problem.  University administrators are interested in determining the average parking time (i.e., the average length of time it takes students to find a place to park on campus) of the students.  An administrator inconspicuously follows 250 students and carefully records their parking times.  Identify the population of interest to the university administration.

As the sample size (n) increases, the variation in the sampling distribution of the sample means increases.

Professors in the Department of Animal Sciences want to estimate the average length of time it takes students to complete a class project correct to within 5 hours with a 98% level of confidence.  Determine the sample size needed to estimate the average length of time required to complete the project to within 5 hours with a 98% level of confidence.  They do not know the standard deviation of the times, but they remember that last year the shortest amount of time needed to complete the project was 5 hours and the longest amount of time was 29 hours.

The owner of Get-A-Way Travel has recently surveyed a random sample of 385 customers of the agency.  He would like to determine if the mean age of the agency’s customers is over 31 years.  If so, he plans to alter the destination of their special cruises and tours.  If not, no changes will be made.  He therefore wants to test:    Ho:  μ = 31 years    Ha:  μ > 31 years If he concludes that the mean age is not over 31 years when in fact it is over 31 years, he makes a ________ error.