A factory produces steel cables, whose resilience follows a normal distribution of unknown mean and standard...

A factory produces steel cables, whose resilience follows a normal distribution of unknown mean and standard deviation σ = 10 KJ / m3. A sample of 100 pieces was taken and through a statistical study a confidence interval (898.04 - 901.96) was obtained for the average resilience of the steel cables produced in the factory.

a) Calculate the value of the average resilience of the 100 pieces of the sample.

b) Calculate the confidence level with which this interval has been obtained.

c) If you want to have an error of 3 KJ / m3 in the confidence interval, what size should the sample be?

Expert Solution

orchestra answered 1 year ago

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