(04.06 MC) The grades on the last history exam had a mean of 80%. Assume the population of grades on history exams is known to be distributed Normally, with a standard deviation of 5%. Approximately what percent of students earn a score between 70% and 80%? (4 points)
Read Details(05.04 HC) A program was created to randomly choose customers at a shoe store to receive a discount. The program claims 15% of the receipts will get a discount in the long run. The manager of the shoe store is skeptical and believes the program’s calculations are incorrect. She selects a random sample and finds that 12% received the discount. The confidence interval is 0.12 ± 0.05 with all conditions for inference met.Part A: Using the given confidence interval, is it statistically evident that the program is not working? Explain. (3 points)Part B: Is it statistically evident from the confidence interval that the program creates the discount with a 0.15 probability? Explain. (2 points)Part C: Another random sample of receipts is taken. This sample is six times the size of the original. Twelve percent of the receipts in the second sample received the discount. What is the value of margin of error based on the second sample with the same confidence level as the original interval? (2 points)Part D: Using the margin of error from the second sample in part C, is the program working as planned? Explain. (3 points) (10 points)
Read Details(04.02 MC) A coin is weighted so the probability of heads is 0.65. The coin is tossed 15 times, and the number of times heads shows is recorded. This procedure is repeated 100 times with the number of times heads shows noted each time. What kind of distribution is simulated? (4 points)
Read Details