Question

(a) A filling process is designed to fill tomato paste cans with 200g of tomato paste. The standard deviation of the filling process is 24g. It is deemed out of order if the average weight of content is different from 200g. To test the filling process, samples of 36 cans are selected at random and the average weight is calculated. Suppose a sample produces a mean weight of 204g. Based on this sample result can you conclude the filling process is out of adjustment at a = 10%? Conduct a test using the p-value approach.

(b)?Powercell batteries claim that their D size batteries have an average life longer than 14 hours. A sample of 8 mechanical boxing rabbits is tested using the Powercell batteries with the following life times recorded in hours:

??14.5? 13.8? 13.2? 14.6? 13.9? 14.0? 13.7? 14.8

Test to determine if Powercell’s claim is true at 5% using the critical value approach.

In your working, make sure you include all six steps of hypothesis testing and state any assumption you have to make. You are also encouraged to include diagrams in your working.

Answer 1