# Solving for Confidence Intervals

Question: A sample of 240 observations is selected from a normal population for which the population standard deviation is known to be 24.The sample mean is 20.

(a) Determine the standard error of the mean. (Round your answer to 3 decimal places)

(b) Determine the 90% confidence interval for the population mean. (Round your answer to 3 decimal places)

https://brainmass.com/statistics/confidence-interval/solving-confidence-intervals-514974

#### Solution Preview

a) Standard error of the mean = population standard deviation/sqrt (sample size) ...

#### Solution Summary

The expert examines solving for confidence intervals for 240 observations.

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