Exam 9: Hypothesis Tests

A student believes that the average grade on the final examination in statistics is at least 85.She plans on taking a sample to test her belief.The correct set of hypotheses is

The average monthly rent for one-bedroom apartments in Chattanooga has been $800.Because of the downturn in the real estate market, it is believed that there has been a decrease in the average rental.The correct hypotheses to be tested are

Identify the null and alternative hypotheses for the following problems. a. The manager of a restaurant believes that it takes a customer less than or equal to 25 minutes to eat lunch. b. Economists have stated that the marginal propensity to consume is at least 90¢ out of every dollar. c. It has been stated that 75 out of every 100 people who go to the movies on Saturday night buy popcorn.

A carpet company advertises that it will deliver your carpet within 15 days of purchase.A sample of 49 past customers is taken.The average delivery time in the sample was 16.2 days.The standard deviation of the population (σ) is known to be 5.6 days. a. State the null and alternative hypotheses for a test to determine if their advertisement is legitimate. b. Using the critical value approach, test the hypotheses.Let α = .05. c. Using the p-value approach, test the hypotheses at the 5% level of significance.

If the level of significance of a hypothesis test is raised from .01 to .05, the probability of a Type II error will

Which of the following does not need to be known in order to compute the p-value?

Read the t statistic from the t distribution table and choose the correct answer.For a one-tailed test (upper tail), using a sample size of 14, and at the 5% level of significance, t =

A grocery store has an average sales of $8000 per day.The store introduced several advertising campaigns in order to increase sales.To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 100 days of sales was selected.It was found that the average was $8200 per day.From past information, it is known that the standard deviation of the population is $1500.The p-value is

A juice drink filling machine, when in perfect adjustment, fills the bottles with 12 ounces of drink on an average.Any overfilling or underfilling results in the shutdown and readjustment of the machine.To determine whether or not the machine is properly adjusted, the correct set of hypotheses is