QCEVault

Sampling and proportions — Question 376

Original QCE Vault practice · 5 marks

Q376 · Practice questionTechnology-activeComplex familiar5 marks

QUESTION 376 (5 marks)

A population proportion is greater than 0.50.5. For independent random samples of size 100100, the standard deviation of the sample proportion is 0.040.04.
a)
Determine the population proportion.
[3 marks]
b)
Use a normal approximation without continuity correction to estimate P(p^>0.85)P(\widehat p>0.85), to four decimal places.
[2 marks]
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