# Question: A compressor manufacturer is testing two different designs for an

A compressor manufacturer is testing two different designs for an air tank. Testing involves pumping air into a tank until it bursts, then noting the air pressure just prior to tank failure. Four tanks of design A are found to fail at an average of 1400 pounds per square inch (psi), with a standard deviation of 250 psi. Six tanks of design B fail at an average of 1620 psi, with a standard deviation of 230 psi. Assuming normal populations with equal standard deviations, use the 0.10 level of significance in comparing the two designs. Construct and interpret the 90% confidence interval for the difference between the population means.

## Answer to relevant Questions

An industrial engineer has designed a new workstation layout that she claims will increase production efficiency. For a sample of 8 workers using the new workstation layout, the average number of units produced per hour is ...A sample of 25 production employees has been tested twice on a standard test of manual dexterity. The average change in the time required to finish the test was a decrease of 1.5 minutes, with a standard deviation of 0.3 ...An Internal Revenue Service manager is comparing the results of recent taxpayer interviews conducted by two auditors. Of 200 taxpayers audited by Ms. Smith, 30% had to pay additional taxes. Of 100 audited by Mr. Burke, only ...Given the information in Exercise 11.76, and using the 0.01 level of significance in comparing the sample standard deviations, were we justified in assuming that the population standard deviations were equal? Would your ...For the one-way ANOVA model, xij = μ + τj + εij, explain the meaning of each term in the equation, then use the appropriate terms from the equation in presenting and explaining the null and alternative hypotheses to be ...Post your question