Posted by Alyssa on .
Scores on the ACT college entrance exam are Normally distributed with a mean µ = 20 and standard deviation σ = 5. An SRS of 25 ACT scores is selected, construct a 95% Confidence Interval for the sample mean (XBar) and interpret your result.

statistics 
PsyDAG,
95% = mean ± 1.96 SEm
SEm = SD/√n
I'll let you do the calculations and interpretations.