QCEVault

Sampling and proportions — Question 313

Original QCE Vault practice · 4 marks

Q313 · Practice questionTechnology-freeSimple familiar4 marks

QUESTION 313 (4 marks)

Two random-sampling procedures estimate the same population proportion p=0.6p=0.6. Procedure A uses n=100n=100 and procedure B uses n=400n=400.
Two sampling densities centred at 0.6. Solid curve A is wider; dashed curve B is narrower and taller.
a)
Determine the standard deviation of the sample proportion for each procedure.
[2 marks]
b)
Explain how the change in sample size affects the sampling distribution.
[2 marks]
Question linkSyllabus coverage

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