QCEVault

Interval estimates for proportions — Question 50

Original QCE Vault practice · 6 marks

Q50 · Practice questionTechnology-activeComplex unfamiliar6 marks

QUESTION 50 (6 marks)

Two independent surveys estimate population proportions. Survey A has n=400n=400 and p^=0.52\hat p=0.52. Survey B has n=900n=900 and p^=0.48\hat p=0.48. Construct approximate 95% confidence intervals for both proportions using z=1.96z=1.96. State whether the intervals overlap, and explain whether overlap alone proves that the two population proportions are equal.
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