Quiz

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Question 1(0.25 points)

As the sample size _____, the standard deviation of the population of all sample means decreases.

Question 1 options:

	increases
	decreases
	remains constant

Question 2(1 point)

According to a Bureau of Labor Statistics, a worker in the U.S. spends on average 528 minutes a day on the job. Suppose the standard deviation of the time spent on the job is 36 minutes. What is the probability that a sample of 81 workers have a mean time more than 533 minutes?

Question 2 options:

	0.8944
	0.1056
	0.4448
	0.5552

Question 3(1 point)

A strength training program was administered to a population of marine recruits. The change in number of push-ups completed between the beginning and end of the program was approximately normally distributed with a mean improvement of 7.2 with a standard deviation of 2.5. What is the probability that a sample of 25recruits will have a mean improvement of less than 8push-ups? Round your answer to 3decimal places.

Question 3 options:

Question 4(1 point)

The amount of corn yield is normally distributed with a mean of 186.7 bushels of corn per acre, with a standard deviation of 25.6 bushels of corn. In an agricultural study, 100 randomly selected acres were harvested. What is the probability that the mean corn yield of these 100 acres is more than 190 bushels of corn? Round your answer to 3 decimal places.

Question 4 options:

Question 5(0.75 points)

Please upload a sketch of the sampling distribution to support your answer in the problem above. Be sure to label

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