Answer to Question #2454 in Statistics and Probability for Stacey Appleton
A random sample of 90 students at a private high school is tested and a mean SAT score of 1030 is obtained. The average score for public high school student is 1000 (σ= 200).
Compute Z obt
Zobt = (x - μ)/(σ /√ n) = (1030 - 1000)/(200/√90) = 1.42