Question: A district official intends to use the mean of a
A district official intends to use the mean of a random sample of 150 sixth graders from a very large school district to estimate the mean score that all the sixth graders in the district would get if they took a certain arithmetic achievement test. If, based on experience, the official knows that σ = 9.4 for such data, what can she assert with probability 0.95 about the maximum error?
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