A survey of 50 students in a school found that they spent an average of 3 hours per day on their smartphones with a standard deviation of 0.5 hours. Calculate a 95% confidence interval for the average time all students in the school spend on their smartphones daily.
Added by Margaret P.
Step 1
It is: Confidence Interval = X ± Z * (σ/√n) Where: X = sample mean Z = Z score (which corresponds to the desired confidence level) σ = standard deviation n = sample size In this case: X = 3 hours σ = 0.5 hours Show more…
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