A statistic and a margin of error is given. Find the confidence interval. Round your answer to the nearest tenth if needed. a. Statistic: 77 margin of error: 2.9
The confidence interval can be found by subtracting the margin of error from the statistic on the lower end, and adding the margin of error to the statistic on the upper end.
Lower end: 77 - 2.9 = 74.1
Upper end: 77 + 2.9 = 79.9
The confidence interval is approximately (74.1, 79.9).