QCEVault

Statistical inference — Question 100

Original QCE Vault practice · 6 marks

Q100 · Practice questionComplex familiar6 marks

QUESTION 100 (6 marks)

A sample of size 64 has xˉ=42.6\bar x=42.6 and s=5.2s=5.2.
a)
Using z=1.96z=1.96, determine an approximate 95% confidence interval for the population mean.
[3 marks]
b)
Assuming s≈5.2s\approx5.2 for planning purposes, determine the smallest sample size required for a margin of error no greater than 0.8 at the same confidence level.
[3 marks]
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