A Gallup survey of 2322 adults (at least 18 years old) in the U. S. found that 408 of them have donated blood in the past two years. Construct a 90% confidence interval for the population proportion of adults in the U. S. who have donated blood in the past two years. Round your answer to three decimal places.

aA 90% confidence interval for the population proportion of adults in the U.S. who have donated blood in the past two years = (0.163,0.189)

Step-by-step explanation:

Let p = population proportion of adults in the U.S. who have donated blood in the past two years.

Given: A Gallup survey of 2322 adults (at least 18 years old) in the U.S. found that 408 of them have donated blood in the past two years.

Sample size: n= 2322

Sample proportion

Critical z-value for 90% confidence level : z*=1.645

The confidence interval for population proportion:

A 90% confidence interval for the population proportion of adults in the U.S. who have donated blood in the past two years:

Hence,