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Statistical inference — Question 236

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Q236 · Practice questionTechnology-activeSimple familiar1 mark

QUESTION 236

Independent observations have a non-normal population with mean 5 and standard deviation 6. For n=144, which is justified by the central limit theorem? In N(a,b), b is variance.
(A)
X‾\overline X has standard deviation 6/1446/144.
(B)
X‾\overline X is approximately N(5,0.25)N(5,0.25) and P(X‾>6)≈0.0228P(\overline X>6)\approx0.0228.
(C)
X‾\overline X is exactly N(5,0.25)N(5,0.25) because sample means are always normal.
(D)
X‾\overline X is approximately N(5,36)N(5,36).
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