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Statistical inference — Question 4

QCAA 2025, Paper 1 · 1 mark

Q4 · 2025 · Technology-freeSimple familiar1 mark

QUESTION 4

XX is a random variable with mean μ\mu and standard deviation σ\sigma. From random samples of XX values, each of size nn, the sample mean is calculated. This sampling and calculation is repeated a large number of times. The mean of the distribution of the sample means would be approximately
(A)
xˉn\dfrac{\bar x}{n}
(B)
μn\dfrac{\mu}{\sqrt n}
(C)
xˉ\bar x
(D)
μ\mu
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