Answer:
the confidence interval of the survey results is (18%, 26%). We can interpret this interval as follows: We are 90% confident that the true percentage of adults from the region who are very likely to watch some coverage of the sporting event on television is between 18% and 26%.
Explanation:
The survey polled 1400 adults from the region and found that 22% of them were very likely to watch some coverage of a certain sporting event on television. The margin of error was plus or minus 4 percentage points with a 90% level of confidence.
(a) To state the survey results in confidence interval form, we can use the formula:
Confidence interval = sample statistic +/- margin of error
where the sample statistic is the percentage of adults who were very likely to watch the sporting event on television, and the margin of error is 4 percentage points.
Substituting the given values, we get:
Confidence interval = 22% +/- 4%
To calculate the endpoints of the interval, we need to add and subtract the margin of error from the sample statistic:
Lower endpoint = 22% - 4% = 18%
Upper endpoint = 22% + 4% = 26%
Therefore, the confidence interval of the survey results is (18%, 26%). We can interpret this interval as follows: We are 90% confident that the true percentage of adults from the region who are very likely to watch some coverage of the sporting event on television is between 18% and 26%.