Data Set 8-1: A sample with scores: 1, 2, 3
-Refer only to Data Set 8-1. The 95 percent confidence interval about this sample mean is
A) 1.20 to 2.80
B) -.43 to 3.43
C) -2.30 to 6.30
D)-0.48 to 4.48

Question

Quizplus · Accepted Answer

The sample mean is 2. The sample standard deviation is 1. The sample size is 3. The t-value for a 95% confidence interval with 2 degrees of freedom is 4.303. The margin of error is 4.303 * 1 / sqrt(3) = 2.48. The 95% confidence interval is 2 +/- 2.48 = -0.48 to 4.48.

Data Set 8-1: a Sample with Scores: 1, 2, 3