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Statistical inference — Question 5

Original QCE Vault practice · 1 mark

Q5 · Practice questionSimple familiar1 mark

QUESTION 5

A confidence interval for a population mean is calculated from a sample of size 64.

The population standard deviation and the zz-value are unchanged. To halve the width of the confidence interval, the required sample size is

(A)
32.
(B)
64.
(C)
128.
(D)
256.
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