Chapter 17, Problem 56E

Third load of wash In Exercise 54, we saw a 98% confidence interval of ( −40, −22) minutes for μ_Top − μ_Front, the difference in time it takes top-loading and front-loading washers to do a load of clothes. Explain why you think each of the following statements is true or false:

1. a) 98% of top loaders are 22 to 40 minutes faster than front loaders.
2. b) If I choose the laundromat’s top loader, there’s a 98% chance that my clothes will be done faster than if I had chosen the front loader.
3. c) If I tried more samples of both kinds of washing machines, in about 98% of these samples I’d expect the top loaders to be an average of 22 to 40 minutes faster.
4. d) If I tried more samples, I’d expect about 98% of the resulting confidence intervals to include the true difference in mean cycle time for the two types of washing machines.
5. e) I’m 98% confident that top loaders wash clothes an average of 22 to 40 minutes faster than front-loading machines.