11. The bank credit card department of Carolina Bank knows from experience that 5% of the card holders have had some high school, 15% have completed high school, 25% have had some college, and 55% have completed college. Of the 500 card holders whose cards have been called in for failure to pay their charges this month, 50 had some high school, 100 had completed high school, 190 had some college, and 160 had completed college. Can we conclude that the distribution of card holders who do not pay their charges is different from all others? Use the .01 significance level.
23. In the early 2000's the Deep Down Mining Company implemented new safety guidelines. Prior to these new guidelines, management expected there to be no accidents in 40% of the months, one accident in 30% of the months, two accidents in 20% of the months, and three accidents in 10% of the months. Over the last 10 years, or 120 months, there have been 46 months in which there were no accidents, 40 months in which there was one accident, 22 months in which there were two accidents, and 12 months in which there were 3 accidents. At the .05 significance level can the management at Deep Down conclude that there has been a change in the monthly accident distribution?
The solution provides step by step method for the calculation of chi squares test statistic. Formula for the calculation and Interpretations of the results are also included.