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Suppose that for some population, intelligence scores are distributed normally with σ = 15 and with...

Suppose that for some population, intelligence scores are distributed normally with σ = 15 and with μ unknown. To
construct a confidence interval for μ, based on the mean of a sample, how large a sample of scores is necessary so
that the probability that μ is within 3 points of the sample mean is:

a) 0.8?

b) 0.96?

c) 0.999?

math   Statistics-And-Probability   
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Answer #1

WuuuUUUUUU Solo : =15 9). C=804. = 080, E = 3 P(x-3 <l<x+3)=0.80 n=1&a12 (o) 12 = / 1.28 * 15 12 3. = 40.96 x 41 Ansin 241]

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