QCEVault

Interval estimates for proportions — Question 316

Original QCE Vault practice · 4 marks

Q316 · Practice questionTechnology-activeSimple familiar4 marks

QUESTION 316 (4 marks)

In a random sample of 500500 residents, 280280 support a pedestrian bridge. A councillor claims that more than half of all residents support it. Use z=1.96z=1.96.
a)
Construct a 95%95\% approximate confidence interval, with endpoints to three decimal places.
[3 marks]
b)
Evaluate the councillor's claim using the interval.
[1 mark]
Question linkSyllabus coverage

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