Question

A poll showed the approval rating to be 0.45 ​(45 ​%). A second poll based on 2500 randomly selected voters showed that 1185 approved of the job the president was doing. Do the results of the second poll indicate that the proportion of voters who approve of the job the president is doing is significantly higher than the original​ level? Explain. Assume the alpha equals0.05 level of significance.

Answer 1

Explanation:

Given that a poll showed the approval rating to be 0.45 ​(45 ​%)

Second poll n =2500: sample p = 1185/2500 = 0.474

H0: p = 0.45

Ha: p not equals 0.45

(Two tailed test)

p difference = 0.024

z-statistic 0.179

Significance level P = 0.8577

95% CI of observed proportion 0.24% to 0.83%

Since p>0.05 we accept null hypothesis

The results of the second poll do not indicate that the proportion of voters who approve of the job the president is doing is significantly higher than the original​ level