Which of the following will make a 95% confidence interval for a population mean narrower?

For which of the following situations would the Central Limit Theorem for Sample Means APPLY?

Select ALL correct answers:

In a survey of eating habits, 3800 national adults were selected randomly and contacted by telephone. Respondents were asked, “Typically, how many times per week do you purchase food at a fast-food restaurant or convenience store?” It was found that, on average, those surveyed purchased food at a fast-food restaurant or convenience store 2.4 times per week.

Suppose the researchers that conducted the survey described above are not convinced and decide to make it a long term study. They conducted the same telephone survey many times over a long period of time, each time they would calculate the mean number of times those surveyed purchased food at fast-food restaurant or convenience store. Five years later, after finding the average of over 30 similar telephone surveys, they published a result that states, on average, adults are likely to purchase food at a fast-food restaurant or convenience store 2.8 times per week.

The latest result is believed to be closer to the real number of times an adult would purchase food at a fast-food restaurant or convenience store per week due to

In a survey of eating habits, 3800 adults were selected randomly and contacted by telephone. Respondents were asked, “Typically, how many times per week do you purchase food at a fast-food restaurant or convenience store?” On average, those surveyed purchased food at a fast-food restaurant or convenience store 2.4 times per week.

Suppose the researchers that conducted the survey described above decide to conduct it again, but will now interview only 2200 people. In the first survey, their sample average value was 2.4. Which of the following is true about the sample average value for the second survey?

Eggs that are contaminated with salmonella can cause food poisoning among consumers. A large egg producer takes an SRS of 200 eggs from all the eggs shipped in one day. The laboratory reports that 11 of these eggs had salmonella contamination. Unknown to the producer, 0.2% (two-tenths of one percent) of all eggs shipped had salmonella. In this situation, match the following to the correct classifications.

Match each term below with the relevant value: 

Oil consumption is increasing at a rate of 2.2% per year. What is the doubling time for the consumption of oil at this rate?

Give your answer to the nearest integer.

How many days late are you starting the project?

A university housing office sends an online survey about dormitory quiet hours to all 5,000 campus residents. Only 200 students complete the survey, and 90% of them request stricter noise enforcement. Which of the following best describes the primary limitation of this study?

A study investigates the impact of two independent variables on student test scores: study environment (Quiet Room vs. Background Music) and study duration (1 hour vs. 3 hours). Participants are randomly assigned to one of the possible treatment combinations. Which experimental design is this?