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A box of Mr. Phipps Tater Crisps is supposed to contain 156 grams of potato chips.  On the side of the box it says “This package is sold by weight, not by volume.  Packed as full as practicable by modern automatic equipment, it contains full net weight indicated.  If it does not appear full when opened, it is because contents have settled during shipping and handling”.  Periodically, the Nabisco Company receives complaints that their boxes of Tater Crisps are not full (i.e., that they contain less than 156 grams of potato chips).  To test this claim, the Nabisco Company randomly samples 10 boxes and finds the average amount of potato chips held by the 10 boxes is 154 grams and the standard deviation is 30 grams. Using a significance level of α = 0.05, find the rejection region for the test of the null hypothesis.

Assume that the mean length of time required to complete the Columbus Marathon was 4.5 hours.  Further assume that the standard deviation of the times required to complete the race was 0.50 hours.  The winning time was 2.3 hours.  Calculate the z-score for the runner with the winning time of 2.3 hours.  Based on this z-score, is this time of 2.3 hours an outlier?  Why or why not?

For a given sample size, the width of the confidence interval for a parameter increases as the confidence coefficient increases.  In other words, a 95% confidence interval is wider than a 90% confidence interval, and a 99% confidence interval is wider than a 95% confidence interval.

A population of turkeys has a mean weight of 20 lb and a standard deviation of the weights equal to 4 lb.  A turkey breeder selects a large number of samples of 36 turkeys each, calculates the mean weight of the turkeys in each of these samples, and then graphs the sample means. Regardless of the shape of the distribution of the population of turkey weights, would we expect the sample means to be approximately normally distributed?

Find the standard deviation of a binomial probability distribution with a sample size of n = 40 and a probability of success of 0.60.

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.  Construct a 98% confidence interval for the true population proportion (p).

Suppose that a random sample of 40 measurements is selected from a population with a mean of 64 and a variance of 64.  What is the mean and standard deviation of the sampling distribution of the sample mean?

Humans possess two sex chromosomes.  A copy of one or the other (equally likely) is contributed to each offspring.  Males have one X chromosome and one Y chromosome.  Females have two X chromosomes.  If a couple has 3 children, what is the probability that they will have at least one boy?

Find the standard deviation of a binomial probability distribution with a sample size of n = 50 and a probability of success of 0.30.

Assume that the mean length of time required to complete the Columbus Marathon was 4.5 hours and that the standard deviation of the times was 0.50 hours.  Assume that the racing times were approximately normally distributed.  What is the probability that a randomly selected runner completed the race in less than 3.6 hours?