Question

On the basis of a survey of 545 television viewers, a statistician has constructed a confidence interval and estimated that the proportion of people who watched the season premiere of Glee is between .16 and .24. What level of confidence did the statistician use in constructing this interval?

Answer 1

0.98 also 98%

Explanation:

In this question we have the Lower limit to be 0.16

We have the Upper limit to be 0.24

Such that (0.16+0.24)/2 = 0.40/2 = 0.20

Standard deviation= √(0.2x0.8/545) this gives 0.017134

Next we get margin of error

Margin of error = 0.24-0.20 = 0.04

Z multiplied by sd =0.04

Such that

Z = 0.04/0.017134 =2.33

On this z score, the Corresponding level of confidence is 0.98

Which is 98%