A market researcher for a consumer electronics company wants to study the media

viewing behavior of residents of a particular area. A random sample of 40

respondents is selected, and each respondent is instructed to keep a detailed record

of time spent engaged viewing content across all screens (traditional TV, DVD/Blu-

ray, game console, Internet on a computer, video on a computer, video on a smart-

phone) in a particular week. The results are as follows:

• Content viewing time per week: = 15 hours, S = 3.5 hours.
• 32 respondents have high definition (HD) on at least one television set.

a. Construct a 95% confidence interval estimate for the mean content viewing time

per week in this area.

b. Construct a 95% confidence interval estimate for the population proportion of

residents who have HD on at least one television set.