Question

The New York Times and CBS News conducted a nationwide poll of 1048 randomly selected 13- to 17-year-olds. Of these 1063 teenagers, 689 had a television in their room.

a) Construct 99% confidence interval for the proportion of all people in this age group who had a TV in their room at the time of the poll

b) Of the 1048 teens surveyed, 189 named Fox as their favorite television network. Give a 95% confidence interval for the proportion of all people in this age group who would choose Fox as their favorite network

Answer 1

a).given data are:-

sample size(n) = 1063

sample proportion () = 689/1063 = 0.6482

z critical value for 99% confidence level, both tailed test be:-

the 99% confidence interval for the proportion of all people in this age group who had a TV in their room at the time of the poll is:-

b).given data are:-

sample size(n) = 1048

sample proportion () = 189/1048 = 0.1803

z critical value for 95% confidence level, both tailed test be:-

the 95% confidence interval for the proportion of all people in this age group who would choose Fox as their favorite network is:-

[ as nothing is mentioned i have rounded off the final answers to 3 decimal places ]

***in case of doubt, comment below. And if u liked the solution, please like.