# Question

Two machines are supposed to be producing steel bars of approximately the same length. A sample of 35 bars from one machine has an average length of 37.013 inches, with a standard deviation of 0.095 inches. For 38 bars produced by the other machine, the corresponding figures are 36.974 inches and 0.032 inches. Using the 0.05 level of significance, test the null hypothesis that the population means are equal. Using the appropriate statistical table, what is the approximate p-value for this test? Construct and interpret the 95% confidence interval for the difference between the population means.

## Answer to relevant Questions

Observing a sample of 35 morning customers at a convenience store, a researcher finds their average stay in the store is 3.0 minutes, with a standard deviation of 0.9 minutes. For a sample of 43 afternoon customers, the mean ...Media observers have been examining the number of minutes devoted to business and financial news during the half-hour evening news broadcasts of two local television channels. For each channel, they have randomly selected 10 ...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 ...Three different point-of-purchase displays are being considered for lottery ticket sales at a chain of convenience stores. Two different locations within the store are also being considered. Eighteen stores for which lottery ...For the experiment described in Exercise 12.8, what null and alternative hypotheses would be appropriate for the one-way ANOVA to examine the data? If the data are as shown here, what conclusion would be reached at the 0.01 ...Post your question

0