Question 693968
A researcher is interested in estimating the noise levels in decibels at area urban hospitals. She wants to be 95% confident that her estimate is correct. If the standard deviation is 5.48, how large a sample is needed to get the desired information to be accurate within 0.68 decibels? Show all work. 
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n = [z*s/E]^2
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n = [1.96*5.48/0.68]^2 = 250 when rounded up
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Cheers,
Stan H.