Answer Happy

2. A new type of band has been developed by a dental laboratory for children who have to wear braces. The new bands are designed to look better, be more comfortable, and provide more rapid progress in realigning teeth. An experiment was conducted to compare the mean wearing time necessary to correct a specific type of misalignment between the old braces and the new bands. Two hundred children were randomly assigned, 100 to each group. A summary of the data is given below. = Old Braces: ni= 100,_sample mean = 425, S1 = 45 days; New Bands: n2= 100, sample mean = 385, S2 = 60 days; = You are interested in conducting a test to determine if the population mean wearing times differ using a=0.10. (i) Write down the research hypothesis (ii) Write down the test formula (do not calculate test score) (iii) Find the rejection region