Unit 7 Review Game

A company that manufactures laptop batteries claims the mean battery life is 16 hours. Assuming the distribution of battery life is approximately normal, a consumer group will conduct a hypothesis test to investigate whether the battery life is less than 16 hours. The group selected a random sample of 14 of the batteries and found an average life of 15.6 hours with a standard deviation of 0.8 hour.

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

A consumer group selected 100 different airplanes at random from each of two large airlines. The mean seat width for the 100 airplanes was calculated for each airline, and the difference in the sample mean widths was calculated. The group used the sample results to construct a 95 percent confidence interval for the difference in population mean widths of seats between the two airlines.

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

A group of AP Chemistry students debated which fast-food chain had better quality bags, Fast Food Chain W or Fast Food Chain M . They decided to investigate by selecting a random sample of 25 bags from each fast food restaurant, slowly adding water until each bag began to leak, and recording the volume of water they were able to pour into each bag. They then calculated the mean volume and standard deviation, in ounces, for the two types of bags.

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

A travel company is investigating whether the average cost of a hotel stay in a certain city has increased over the past year. The company recorded the cost of a one-night stay for a Friday night in January of the current year and in the previous year for 31 hotels selected at random. The difference in cost (current year minus previous year) was calculated for each hotel.

Which of the following is the appropriate test for the company’s investigation?

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

An experiment was conducted to investigate whether there is a difference in mean bag strengths for two different brands of paper sandwich bags. A random sample of 50 bags from each of Brand X and Brand Y was selected. Each bag was held from its rim, and one-ounce weights were dropped into the bag one at a time from the same height until the bag ripped. The number of ounces the bag held before ripping was recorded, and the mean number of ounces for each brand was calculated.

Which of the following is the appropriate test for the study?

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

Two ride-sharing companies, A and B, provide service for a certain city. A random sample of 52 trips made by Company A and a random sample of 52 trips made by Company B were selected, and the number of miles traveled for each trip was recorded. The difference between the sample means for the two companies (A−B) was used to construct the 95 percent confidence interval (1.86,2.15).

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

A recent newspaper article claimed that more people read Magazine A than read Magazine B. To test the claim, a study was conducted by a publishing representative in which newsstand operators were selected at random and asked how many of each magazine were sold that day. The representative will conduct a hypothesis test to test whether the mean number of magazines of type A the operators sell, μA, is greater than the mean number of magazines of type B the operators sell, μB.

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

The mean number of sick days per employee taken last year by all employees of a large city was 10.6 days. A city administrator is investigating whether the mean number of sick days this year is different from the mean number of sick days last year. The administrator takes a random sample of 40 employees and finds the mean of the sample to be 12.9. A hypothesis test will be conducted as part of the investigation.

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

A consumer agency is interested in examining whether there is a difference in two common sealant products used to waterproof residential backyard decks. With cooperation of several builders in the area, they randomly assign 38 newly constructed decks to be treated with Very Clear deck sealant and another 37 newly constructed decks to be treated with Sure Seal deck sealant. After one year of being exposed to similar weather conditions, the decks are rated on a scale of 1 to 100. The mean rating for the decks treated with Very Clear is 89.2 with a standard deviation of 3.1. Estimate the population mean rating for all decks treated with Very Clear.

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis

A marketing executive is investigating whether this year’s advertising campaign has resulted in greater mean sales compared with last year’s mean sales. The executive collects a random sample of 100 customer orders from a large population of orders and calculates the sample mean and sample standard deviation.

Which of the following is the appropriate test for the executive’s investigation?

• 1 sample t interval

• 1 sample t test

• 2 sample t interval

• 2 sample t test

• Matched Pairs analysis