QCEVault

Statistical inference — Question 102

Original QCE Vault practice · 6 marks

Q102 · Practice questionComplex familiar6 marks

QUESTION 102 (6 marks)

Two independent samples from the same type of population give the following summaries. SamplenxˉsA10075.210B40074.810\begin{array}{c|ccc}\text{Sample}&n&\bar x&s\\\hline A&100&75.2&10\\B&400&74.8&10\end{array} Using z=1.96z=1.96:
a)
Determine a 95% confidence interval for the population mean from each sample.
[4 marks]
b)
Compare the precision of the two intervals and comment on a proposed value μ=76\mu=76.
[2 marks]
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