Opre 6301 Test 2 |74 Questions| With Correct Answers.

The normal distribution can be used to approximate the sampling distribution of the sample proportion with a probability of success 0.77 if the sample size is greater than or equal to (4 decimal places) {Ans: 21.739 ± 0.1%}The standard error of the mean for a sample of size 180 is 25. In order to cut the standard error of the mean in half (to 12.5) we must select a sample size of {Ans: 720.000 ± 0.1%}why we take samples {Ans: To contact the whole population would be time consuming The cost of studying all the items in a population may be prohibitive The physical impossibility of checking all items in the population The destructive nature of some tests The sample results are adequate}*nonresponse error {Ans: error (or bias) introduced when responses are not obtained from some members of the sample, i.e. the sample observations that are collected may not be representative of the target population}The personnel director at a large company studied the eating habits of the company's employees. The director watched and recorded whether each employee brought his/her own lunch to work, ate at the company cafeteria, or went out to lunch. What method of