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Questions 7 - 9 (3 points each): Use the following scenario to answer the questions. During a shift at a Student Success Learning Center, there are always ve tutors scheduled to help. The following probability mass function represents the number of available tutors (tutors that are not currently helping other students) at any given moment during a single shift. num- ------nm 7. What is the probability there will be three or more tutors available during a given shift? A. 0.17 B. 0.19 C. 0.36 D. 0.83 Answer: 8. How many tutors are expected to be available during a single shift? A. 2.2 B. 2.5 C. 3.0 D. 3.2 Answer: 9. What is the standard deviation for the number of tutors available during a single shift? A. 0.101 B. 1.319 C. 1.740 D. 1.871 Answer: Questions 10 12 (3 points each): Use the following scenario to answer the questions. According to an industrial company's records of 302 accidents, the time in days between accidents has the following distribution. me Between Industrial Accidents Frequency 0 20 40 60 BO 100 | '| I I' | '| I | 0 20 Ill) 60 BO 100 1 20 140 Days 10. Based on the shape of the distribution, what type of probability distribution would be the most appropriate to model days between accidents? A. Binomial B. Exponential C. Normal D. Uniform Answer: 11. The cumulative distribution function for days between accidents is: x F(x) = 1 EVE, forx 2 0 What is the probability the time between accidents is more than 40 days? A. 01025 B. 0.1084 C. 0.8916 D. 0.8975 Answer: 12. Based on F (x) and the distribution of time between accidents, what is the approximate median? A. 0.0274 B. 5.4185 C. 12.4767 D. 18.0