SOLUTION: 3. A standard placement test has a mean of 115 and a standard deviation of mean = 10. Determine the minimum sample size if we want to be 90% certain that we are within 2 points of
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Question 197736: 3. A standard placement test has a mean of 115 and a standard deviation of mean = 10. Determine the minimum sample size if we want to be 90% certain that we are within 2 points of the true mean. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A standard placement test has a mean of 115 and a standard deviation of mean = 10. Determine the minimum sample size if we want to be 90% certain that we are within 2 points of the true mean.
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n = [z*sigma/E]^2
n = [1.645*10/2]^2
n = 67.65
Round up to n = 68
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Cheers,
Stan H.
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