He american heart association is about to conduct an anti-smoking campaign and wants to know the fraction of americans over 45 who smoke. step 2 of 2: suppose a sample of 830 americans over 45 is drawn. of these people, 631 don't smoke. using the data, construct the 85% confidence interval for the population proportion of americans over 45 who smoke. round your answers to three decimal places.

The 85% confidence interval is (0.2187, 0.2613).

Step-by-step explanation:

We have a large sample of size n = 830 Americans over 45. We have observed that 631 people don't smoke. Let p be the population proportion of Americans over 45 who smoke. An point estimate of p is and an estimate of the standard deviation of is = 0.0148. Therefore, because we have a large sample, the 85% confidence interval for the population proportion is given by where is the 7.5th quantile of the standard normal distribution, i.e., -1.4395. Therefore the 85% confidence interval is or equivalently (0.2187, 0.2613).

the answer is d on edge

step-by-step explanation: