The heights of students at Wits follow a Normal distribution with a standard deviation of 0.01m. Twelve students are randomly chosen and their heights are measured yielding a mean of 1.75m. A 90 % confidence interval for the average student height at Wits is:
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Step 1
In this case, we are trying to find the confidence interval for the average student height at Wits. The formula for a confidence interval is: CI = X ± Z * (σ/√n) where: - X is the sample mean - Z is the Z-score (which corresponds to the desired confidence Show more…
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