Use the following information to answer questions (16)-(18). From a random sample of workers at a large
corporation you find that 58% of 200 went on a vacation last year away from home for at least a week.
-Which of the following statements are correct concerning the 95% confidence interval of (0.50, 0.66) of coworkers who went on a vacation last year away from home for at least a week?
A)If the sample size is 500 instead of 200, the confidence interval will be larger.
B)A maximum of 66% of the coworkers went on a vacation last year away from home for at least a week.
C)If the confidence level were changed from 95% to 99%, the confidence interval would become wider.
D)If the confidence level were changed from 95% to 90%, the confidence interval would become wider.

Question

Quizplus · Accepted Answer

The width of a confidence interval is influenced by the confidence level and the sample size. Increasing the confidence level (from 95% to 99%) requires a wider interval to capture the population parameter with higher certainty, hence C is correct. Choices A and D are incorrect because increasing the sample size makes the interval narrower, not larger, and decreasing the confidence level makes the interval narrower, not wider. Choice B misinterprets the confidence interval; it does not imply a maximum percentage of coworkers who went on vacation, but rather an interval estimate of the true proportion.

Use the Following Information to Answer Questions (16)-(18)