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Statistics - Confidence Interval

How do you find the Confidence Interval for a particular Confidence Level, such as 95%, for a sample of more than 30 people? Show the exact formulas that you use in this situation to calculate the sample standard deviation and standard error?

Solution Preview

If the sample size is greater than 30, then we use the normal distribution. A typical problem will have the following


Given: (a) Mean of the sample, M (Say 20) (b) Standard Deviation of the sample, s (Say 1.3) (c) Sample size, n (Say 49)

(d) ...

Solution Summary

Step-by-step solution is provided.