Question

1. It is extremely difficult to make dye bind with recycled paper fibers. This is bad news for two reasons. First, companies are more reluctant to use recycled paper if they are not able to obtain the same quality for their graphics design than the one they obtain using normal paper. Second, when the dye is not binding with the paper it goes to waste which is ultimately bad for the environment. In order to increase the binding of dye, you have designed a new simple procedure. It consists of repeatedly beating up the paper fiber with a mechanical device for 10 minutes before the dying procedure is performed. You took 34 samples of recycled paper, submitted them to your new procedure, dyed them and performed a dye retention test and obtained an average of 35% with a standard deviation of 7%. You took another 34 samples of recycled paper, dyed them and performed a dye retention test and obtained an average of 31% with a standard deviation of 6%. Verify the claim that your new procedure is actually an improvement at the 0.01 level of significance. Include a p-value in your solution.

Answer 1