QUESTION 1 (25 MARKS) a. Given a population has a mean of 125. What is...

QUESTION 1

a. Given a population has a mean of 125. What is the sampling error for an eight items sample with the values 103, 123, 99, 107, 121, 100, 100 and 99?

b. United Manufacturing and Supply makes sprinkler valves for use in residential sprinkler systems. United supplies these valves to major companies such as Rain Bird and Nelson, who in turn sell sprinkler products to retailers. United recently entered into a contract to supply 40,000 sprinkler valves. The contract called for at least 97% of the valves to be free of defects. Before shipping the valves, United managers tested 200 randomly selected valves and found 190 defect-free valves in the sample. If the actual population of 40,000 valves is 97% defect-free, what is the probability of finding 190 or fewer defect-free valves?

c. Suppose a population is normally distributed with a mean 100 and a standard deviation of 15. When a sample of size n = 36 is collected a sampling distribution is created. Explain which is larger: the probability of a value randomly selected from the population being larger than 120, or the probability of a sample mean being larger than 120.

Expert Solution

orchestra answered 1 year ago

A population has a standard deviation of 25 and a mean of 300. Given a random sample of size 100, how likely is it that the sample mean will be within +/- 5 of the population mean?

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