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Sampling and proportions — Question 193

Original QCE Vault practice · 3 marks

Q193 · Practice questionTechnology-activeSimple familiar3 marks

QUESTION 193 (3 marks)

A population proportion is p=0.35p=0.35. For random samples of size 100100, the sampling distribution of p^\hat p is approximated by the normal curve shown. Determine its mean and standard deviation, and estimate P(0.30<p^<0.40)P(0.30<\hat p<0.40).
Approximate normal sampling distribution for sample proportion centred at 0.35 with the region from 0.30 to 0.40 shaded.
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