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Confidence Interval

1) A random sample, size 50, is taken from a large population, measuring the time it takes to complete a race.

The sample mean is 44 minutes, the sample standard deviation 6.7 minutes.

Calculate a 95% confidence interval around the sample mean

2) Do you use the z or t value? What value is used?

3) Interpret the confidence interval in a sentence.

4) Explain why you used either z or t.

Solution Summary

The solution provides step by step method for the calculation of confidence interval for mean. Formula for the calculation and Interpretations of the results are also included.