Question 480117
A consumer agency wants to estimate, at a 99% confidence level, the proportion of all households that own at least one pet. What is the sample size that would limit the maximum error of the estimate to within .03 of the population proportion?
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n = [z/E]^2*pq
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Find the z-value with a 0.005 left tail: z = 2.57
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E = 0.03
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You are not given a value for "p" so you should use p = 1/2,
which is the "least biased" estimate of p.
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n = [2.5758/0.03]^2*(1/4)
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n = 7372.11*(1/4)
n = 1843.02
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Round up to n = 1844
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Cheers,
Stan H.