QCEVault

Interval estimates for proportions — Question 236

Original QCE Vault practice · 5 marks

Q236 · Practice questionTechnology-activeComplex unfamiliar5 marks

QUESTION 236 (5 marks)

In a sample of 500500 customers, 315315 prefer option A. Use z=1.96z=1.96.
a)
Construct an approximate 95%95\% confidence interval for the population proportion.
[3 marks]
b)
Assess the claim that a majority of customers prefer option A.
[2 marks]
Question linkSyllabus coverage

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