Question

A survey of 2297 adults in a certain large country aged 18 and older conducted by a reputable polling organization found that 419 have donated blood in the past two years. Complete parts (a) through (c) below. Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). (a) Obtain a point estimate for the population proportion of adults in the country aged 18 and older who have donated blood in the past two years. p= 182 (Round to three decimal places as needed.) (b) Verify that the requirements for constructing a confidence interval about p are satisfied. The sample can be assumed to be a simple random sample, the value of np(1-0is 341.986 , which is greater than or equal to 10, and the sample size can be assumed to be less than or equal to 5% of the population size. (Round to three decimal places as needed.) (c) Construct and interpret a 90% confidence interval for the population proportion of adults in the country who have donated blood in the past two years. Select the correct choice below and fill in any answer boxes within your choice. (Type integers or decimals rounded to three decimal places as needed. Use ascending order.) O A. We are % confident the proportion of adults in the country aged 18 and older who have donated blood in the past two years is between and OB. There is a % probability the proportion of adults in the country aged 18 and older who have donated blood in the past two years is between and

Answer 1

solution Given that, n = 2291 x = 419 o Point estimate. 419 2297 - 0.182 nê ( -8)= 2297 x 0.182 (1-0.182) = 341.968 The sample can be assumed to be a simple rondom sample, the value of nộC1- ) is 341.968, which is greather than or equal to 10, and the sample size can be assumed to be less then or equal to 5% of the population size. At 96% confidence level the zis, do 1-0.90 0.1 -0.1 -0.05 a 2 2 zge - 20.05 - 1.645 Margin of error 25 E= Zax P. (18) 2 =1.645 0.182 X (1-0.182) 2297 = 0.013

At 90% confidence interval of pis. Å ELP LÊTE 0.182-0.013 LPL0.182 +0.013 0.169 < PLO.195 (0.169, 0.195) :. a) we are 90% confident the proporton of adults in the country aged 18 and older who have donated blood in the past is between 0.169 and 0.195. two years