SOLUTION: What is the sample size needed to be able to estimate the mean dollars that each card holder will spend each month. It would like to be within plus or minus $25 of the true mean wi

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Question 451261: What is the sample size needed to be able to estimate the mean dollars that each card holder will spend each month. It would like to be within plus or minus $25 of the true mean with a 98% confidence level. It would like to be within plus or minus $25 of the true mean with a 98% confidence level. The standard deviation is thought to be $400. How many card holders should be sampled?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What is the sample size needed to be able to estimate the mean dollars that each card holder will spend each month. It would like to be within plus or minus $25 of the true mean with a 98% confidence level. The standard deviation is thought to be $400. How many card holders should be sampled?
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n = [z*s/E]^2
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n = [2.3263*400/25]^2 = 347 when rounded up
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Cheers,
Stan H.
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