1.) a) P Z * P (1-8) P is the sample proportion n n is the sample size Z is the Z-Score associated with the desired level of confidence b.) The Z-Statistic is used in a confidence interval for a Population proportion because the normal distribution is the limiting distribution of the binomial distribution (as we increase the sample size in the binomial distribution, we approximate the hormal distribution). Since proportions are based on the binomial distribution, and the z-statistic Follows the standard normal distribution, then we use the Z-Statistic in a confidence interval for a population proportion. C.) The Conditions needed for a sample to be considered binomial and that it approximates the normal distribution Care: There is a fixed number of "n" independent trials The outcome of any trial is either a success or failure each trial has a constant probability of success "p" np 5 and n(1-p)=5 1.) A. Write out the formula for a confidence interval for a population proportion. (1 point) B. Why is the z-statistic used in a confidence interval for a population proportion? (2 points) What are the conditions a sample needs to meet before you can assume it's binomial and that it approximates a normal distribution? (2 points)