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Suppose x has a binomial probability distribution with n = 150 and p = 0.60.  Use the normal approximation to the binomial to find P(X>100).

A local consumer reporter wants to compare the average costs of grocery items purchased at three different supermarkets – Kroger, Giant Eagle, and Meier.  Prices (in dollars) were recorded for a sample of 60 randomly selected grocery items at each of the three supermarkets.  In order to reduce item-to-item variation, the prices were recorded for each item on the same day at each supermarket. Item                          Kroger    Giant Eagle    Meier     1) Big Thirst Towel      $1.21       $1.49          $1.59 2) Post Golden Crisp    2.78         2.99            3.35 3) Tylenol Tablets         5.98         5.29            5.98           .                              .              .                   .           .                              .              .                   . 59) Colgate Shave       0.94         1.10            1.19 60) Kidney Beans        0.45          0.56            0.38                                                                                   The results of the Analysis of Variance for this experiment are as follows: Source           df       SS            MS          F     Total                       222.21     Supermarket              2.64       1.32       39.23 Item                        215.59       3.65     108.54 Error                           3.97      0.0337                                                                                What are the correct degrees of freedom for total, supermarket, item, and error, respectively?

A bottling company needs to produce bottles that will hold 12 ounces of liquid for a local beer maker.  Periodically, the company receives complaints that their bottles are not holding enough liquid.  To test this claim, the bottling company randomly samples 15 bottles and finds the average amount of liquid held by the 15 bottles is 11.90 ounces and the standard deviation is 0.20 ounces. Using a level of significance of α = 0.05 and a one-tailed hypothesis test, find the appropriate rejection region.

We want to test the hypothesis that the mean yield of a particular variety of corn is less than 150 bushels per acre.  Therefore, we obtain the yields of a random sample of 20 corn fields in which this variety was planted. The average yield of the sample of fields was 140 bushels per acre with a standard deviation of 10 bushels per acre.  We want to test:    Ho:  μ = 150 bushels/acre    Ha:  μ < 150 bushels/acre using a significance level (α) = 0.10. What is the critical value that defines the boundary of the rejection region in this problem?

The sample space for an experiment is the collection of all of the sample points.

What assumption is required for estimating the population mean (μ) when we have small samples of n < 30?

Suppose x has a binomial probability distribution with n = 400 and p = 0.70.  Use the normal approximation to the binomial to find P (X 

According to Chebyshev’s Rule, we expect ________ % of the observations to fall within two standard deviations of the mean, if the data do not have a symmetric and mound shaped distribution.

Assume we are given the following information for yields of corn (in bushels per acre):    Median = 150     Lower quartile = 130     Upper quartile = 170    Lowest yield = 80     Highest yield = 250 Construct a box plot for these data.  Based on this box plot, is the lowest yield of 80 bushels per acre a suspect or highly suspect outlier?

Find the mean of a binomial probability distribution with a sample size of n = 20 and a probability of success of 0.40.