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Chapter 8: Q 44. (page 523)

Age and September 11 Refer to Exercise 42. The study also reported that 86% of

millennials included 9/11 in their top-10 list and 70% of baby boomers included 9/11.

a. Explain why you do not have enough information to give confidence intervals for

millennials and baby boomers separately.

b. Do you think a 95%confidence interval for baby boomers would have a larger or smaller margin of error than the estimate from Exercise 42? Explain your answer.

Short Answer

Expert verified

a. It is because sample size is not given.

b. Margin of error is large.

Step by step solution

01

Ste 1: Given Information

It is given that 85%of millennials includes 9/11in their top 10 and70%for baby boomers included9/11

02

Why we do not have enough information to give confidence intervals formillennials and baby boomers separately

To calculate confidence interval, we require sample size, sample proportion and confidence level. We are not given sample size, so it is not possible to find confidence interval.

03

To check if margin of error is less or large as per given conditions

If sample size decrease, baby boomers in sample is less than total individuals in sample. Hence we will get less information about population, less accurate estimates are obtained. We get less chances of true population proportion containing confidence interval. So, confidence interval is wider. Margin of error is half the width of confidence interval, there will be larger margin of error.

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