Answer to Question #20721 in Statistics and Probability for Amanda Seifert

Question #20721

2. A Nationwide auto insurance manager wants to estimate the proportion of car owners, in a new market area, who purchase at least $1 million of liability coverage in their automobile insurance policies.
a. How large a sample should be chosen to estimate the proportion with a 95% error margin of 0.08?
Suppose the proportion is known to be about p_o=0.15.
b. How large a sample should be chosen to estimate the proportion with a 95% error margin of 0.08
if nothing is known about its value?

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