# Question: A company employs two shifts of workers Each shift produces

A company employs two shifts of workers. Each shift produces a type of gasket where the thickness is the critical dimension. The average thickness and the standard deviation of thickness for shift 1, based on a random sample of 30 gaskets, are 10.53 mm and 0.14 mm. The similar figures for shift 2, based on a random sample of 25 gaskets, are 10.55 mm and 0.17 mm. Let µ1 - µ2 be the mean difference in thickness between shifts 1 and 2.

a. Using the formulas from this section, not StatTools, find a 95% confidence interval for µ1 - µ2.

b. Based on your answer to part a, are you convinced that the gaskets from shift 2 are, on average, wider than those from shift 1? Why or why not?

c. How would your answers to parts a and b change if the sample sizes were instead 300 and 250?

a. Using the formulas from this section, not StatTools, find a 95% confidence interval for µ1 - µ2.

b. Based on your answer to part a, are you convinced that the gaskets from shift 2 are, on average, wider than those from shift 1? Why or why not?

c. How would your answers to parts a and b change if the sample sizes were instead 300 and 250?

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

A company that advertises on the Web wants to know which search engine its customers prefer as their primary search engine: Google or Bing. Specifically, the company wants to know whether the preference depends on the ...You have been assigned to determine whether more people prefer Coke or Pepsi. Assume that roughly half the population prefers Coke and half prefers Pepsi. How large a sample do you need to take to ensure that you can ...Referring to the previous problem, you often hear the results of such a poll in the news. In fact, the newscasters usually report something such as, “44.9% of the population approve or strongly approve of the President’s ...Find a 95% confidence interval for the proportion of all customers whose order is for more than $100. Then do this separately for each of three times of day. Find a 95% confidence interval for the proportion of all bills paid within 15 days. Find a 95% confidence interval for the difference between the proportion of large customers who pay within 15 days and the similar ...Post your question