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If a confidence interval is (24, 50), what is the margin of error (MOE)? [a]

Assume the starting salary at a tech company are normally distributed. A sample of 15 employees at this tech company yielded an average starting salary of $84,500 with a standard deviation of $12,000.   a. What is the point estimate for the average starting salary of ALL employees at this company? [f] b. Find a 95% confidence interval for the population mean starting salary: ([a], [b]) c. Interpret the interval: We are [c]% confident that the average starting salary of ALL employees at this company is between [d] and [e].

A researcher is interested in the proportion of American families that eat dinner together as a family. It was found that 32 out of 100 randomly sampled American families ate dinner together. (Give your answers as decimals and round to 3 decimal places when necessary)   a. What is the point estimate for the proportion of ALL American families that eat dinner together as a family? [a] b. Construct a 90% confidence interval for the proportion of ALL American families that eat dinner together as a family: ([b], [c])

A sample of 50 UNF students revealed that 20 do the majority of their studying in the library. (Give your answers as decimals and round to 3 decimal places when necessary)   a. Provide the point estimate for the proportion of ALL UNF students who do the majority of their studying in the library. [a] b. Calculate a 95% confidence interval for the proportion of ALL UNF students who do the majority of their studying in the library: ([b], [c])

The length of a MLB game in 2019 was normally distributed with a mean of 185 minutes and a standard deviation of 17 minutes. (Round to 3 decimal places).   a. What is the probability that a randomly selected baseball game lasts more than 166 minutes? [a] b. What is the probability that a randomly selected baseball game lasts less than 200 minutes? [b] c. What length represents the 47th percentile? [c] d. What are the two lengths that represent the middle 42%? (Separate your numbers with a comma, put the smaller number first) [d]

If a confidence interval is (14, 80), what is the margin of error (MOE)? [a]

Suppose two people are at a dinner party. There are 3 food options they can choose from – chicken (C), veggie (V), or steak (S). Choose the sample space for the possible food selections from these people.  Sample space = [a]

If P(A) = 0.32, P(B) = 0.45, and P(A and B) = 0.17, are events A and B independent?

A homeowner is interested in the average cost of all bathroom remodels. The homeowner has seen that the average cost is $10,750. The homeowner believes that the average cost of a bathroom model is more than this value. They randomly select 41 bathroom remodel costs, and they find that the average cost was $10,900 with a standard deviation of $450. Use a 5% level of significance to test the homeowner’s belief.   State the hypotheses:

Suppose a group of 3 friends are at a dinner party. There are 2 food options they can choose from – meat (M) or vegetarian (V). Choose the sample space for the possible food selections from this friend group. Sample space = [a]