statistics

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 (X-Bar) and interpret your result.

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1. 95% = mean ± 1.96 SEm

SEm = SD/√n

I'll let you do the calculations and interpretations.

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posted by PsyDAG

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