Question

A simple random sample of 300 voters was polled several months before a presidential election. One of the questions asked was: "Are you satisfied with the choice of candidates for president?" A total of 123 of them said that they were not satisfied. a. What function would you use to create a confident interval for the proportion of voters who are not satisfied with the choice of candidates? b. Create a 99% confident interval for the proportion of voters who are not satisfied with the choice of candidates. Round your values to two decimal places. (

Answer 1

let, X = Nermber of votees said that they were not satisfied with the choice of candidates for president out of na you Here n=300, X = 123 have, 123 300 0.41 n 1-0.41 = 0.59 We have to construct, a 99% confidence interval for the proportion of votes who are not satisfied with the choice of candidates significance level (d) = 0.01 (1.6) know that, a 100 ltd) % confidence interval for true population proportion (p) A Z212 Ê re 9. + Z212. n n ::22/2 = 2001 2.58 The required confidence interval is, 0:41 2.58 0.41 + 2.58 0.41X 0.59 300 0.418o.sg 300 ( 0.34, 0:48) cs