# Question: Calculating a confidence interval for the proportion requires a minimum

Calculating a confidence interval for the proportion requires a minimum sample size. Calculate a confidence interval, using any confidence level of 90% or higher, for the population proportion for each of the following.

a. n = 200 and p̂ = .01

b. n = 160 and p̂ = .9875

Explain why these confidence intervals reveal a problem when the conditions for using the normal approximation do not hold.

a. n = 200 and p̂ = .01

b. n = 160 and p̂ = .9875

Explain why these confidence intervals reveal a problem when the conditions for using the normal approximation do not hold.

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