QCEVault

Interval estimates for proportions — Question 219

Original QCE Vault practice · 6 marks

Q219 · Practice questionTechnology-freeComplex unfamiliar6 marks

QUESTION 219 (6 marks)

A random sample of 225225 voters gives 126126 who support a proposal. Use z=1.96z=1.96 for an approximate 95%95\% confidence interval for the population proportion.
a)
Find the sample proportion.
[1 mark]
b)
Construct the approximate 95%95\% confidence interval.
[3 marks]
c)
Interpret the interval and state one condition required for the approximation.
[2 marks]
Question linkSyllabus coverage

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