A normal population has the mean of 10 and the variance of 100. A random sample of size n = 17 is selected. (a) Find the standard deviation of the sample mean. Round your answer to two decimal places (e.g. 98.76). ?x? = (b) How large must the sample be if you want to halve the standard deviation of the sample mean? n =
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Given: Population variance (σ^2) = 100 Sample size (n) = 17 Standard deviation of the sample mean (σ_x̄) = σ / √n σ_x̄ = √(100 / 17) σ_x̄ ≈ 2.43 Show more…
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