- C A Recent Study On Robberies For A Certain City Xyz Showed An Average Of One Robbery Per 20 000 People If A City Of 1 (39.32 KiB) Viewed 49 times
(c) A recent study on robberies for a certain city XYZ showed an average of one robbery per 20,000 people. If a city of 80,000 people, please identify the probability if three or more robberies were occurred. (d) The average running times of disks produced by Company A is 88.1 minutes and a standard deviation of 6.1 minutes, while Company B obtained a mean running times of 99.3 minutes with a standard deviation of 13.6 minutes. Assume the population are approximately normally distributed. Solve the probability when a random sample of 41 disks from Company B has a mean running times that at most 15 minutes more than the mean running times of a random sample of 32 disks from Company A.