# Question: With reference to Exercise 11 25 use the large sample confidence interval

With reference to Exercise 11.25, use the large-sample confidence- interval formula of Exercise 11.19 to construct a 98% confidence interval for the standard deviation of the time it takes a mechanic to perform the given task.

In exercise

A food inspector, examining 12 jars of a certain brand of peanut butter, obtained the following percent-ages of impurities: 2.3, 1.9, 2.1, 2.8, 2.3, 3.6, 1.4, 1.8, 2.1, 3.2, 2.0, and 1.9. Based on the modification of Theorem 11.1 of Exercise 11.7, what can she assert with 95% confidence about the maximum error if she uses the mean of this sample as an estimate of the average percentage of impurities in this brand of peanut butter?

In exercise

A food inspector, examining 12 jars of a certain brand of peanut butter, obtained the following percent-ages of impurities: 2.3, 1.9, 2.1, 2.8, 2.3, 3.6, 1.4, 1.8, 2.1, 3.2, 2.0, and 1.9. Based on the modification of Theorem 11.1 of Exercise 11.7, what can she assert with 95% confidence about the maximum error if she uses the mean of this sample as an estimate of the average percentage of impurities in this brand of peanut butter?

**View Solution:**## Answer to relevant Questions

With reference to Exercise 11.34, construct a 98% confidence interval for the ratio of the variances of the two populations sampled. In exercise A study of two kinds of photocopying equipment shows that 61 failures of the ...The following are the compressive strengths (given to the nearest 10 psi) of 30 concrete samples. Use a computer program to find a 90% confidence interval for the standard deviation of these compressive strengths. Use the Neyman-Pearson lemma to indicate how to construct the most powerful critical region of size α to test the null hypothesis θ = θ0, where θ is the parameter of a binomial distribution with a given value of n, ...Decide in each case whether the hypothesis is simple or composite: (a) The hypothesis that a random variable has a Poisson distribution with λ = 1.25; (b) The hypothesis that a random variable has a Poisson distribution ...An airline wants to test the null hypothesis that 60 percent of its passengers object to smoking inside the plane. Explain under what conditions they would be committing a type I error and under what conditions they would be ...Post your question