Intraocular pressure (IOP) was measured in 400 people. Mean was found to be 25 mm Hg and Standard detion was recorded 10 mm Hg. 95% Confidence Interval would be?: (A) 22-28, (B) 23-27, (C) 24-26, (D) 21-29
Answer is C. In the given question, Mean (u) = 25 mm Hg standard detion = 10 mm Hg, Z95 = 1.96 (as we are asked 95% CI) Sample size, n =400 Confidence intervals (CI 95) = Mean +- Z95 (SE) CI-95 = 25 +- 1.96 (10/ [?]400) = 24-26 mm Hg