A company that produces and markets video game systems wishes to assess its customers level of satisfaction with a relatively new model, the xyz-box. In the six months since the introduction of the model the company has received 73,219 warranty registrations from purchasers. The company will select a random sample of 65 of these registrations and will conduct telephone interviews with the purchasers. Specifically each purchaser will be asked to state his or her level of agreement with each of the seven statements listed on the survey instrument given in figure 1.6. Here the level of agreement for each statement is measured on a 7 point Likert scale. Purchaser satisfication will be measured by adding the purchasers responses to the seven statements. It follows that for each consumer the minimum composite score possible is 7 and the maximum is 49. Furthermore experience has shown that a purchaser of a video game system is very satisfied if his or her composite score is at least 42. Suppose that when the 65 customers are interviewed their composite scores are as given in table 1.2 below. recall that very satisfied customers give the xyz box video game system a rating that is at least 42.Suppose the manufacturer of the xyz box wishes to use the 65 satisfaction ratings to provide evidence supporting the claim that the mean composite satisfaction rating for the xyz box exceeeds 42. table 1.2 scores are as follows:39,45,38.42,42,41,38,42,46, 44,40,39,40,42,45, and 48, 44,41,45,44,44,44,46, 39,41,44,42,47,43,45, and 47,43,41,40,43,44,41,38,43,36,44,44 ,45,44,46, and 47,44,43,45,45,40,46,41,43,39,43,46 ,45,45,46 and 44,42,46,40,43.1. letting u represent the mean composite satisfaction rating for the xyz-box set up the null and alternative hypotheses needed if the manufacturer wishes to attempt to provide evidence supporting the claim that u exceeds 42.
2. calculate the sample mean and standard deviation of the sample data.
3. determining whether a left, right or two tailed test is performed, use the critical values to test the hypothesis at confidence level of 95%.
4. interpret the results in terms of the evidence that the mean composite satisfaction rating exceeds 42?