Question

1. It can take up to four days to get your computer repaired. The prob- ability of the number of days D it takes to repair has the following probability distribution: Po(d) 0.2,0.5,0.2,0.1, for d 1,2,3,4, respectively. The cost C for the service varies according to D, i.e. C(d) 80, 70, 40, 30, for d 1,2, 3, 4, respectively. Answer the follow- ing questions: (a) (15 pts) Plot the cumulative distribution function (CDF) of D, FD(x), and mark the critical values on your graph. Use the graph to find out Po(d> 2). (15 pts) What is the expected waiting time ?D-ED? (b) (c) (15 pts) Provide the probability mass function (PMF) of the ran- dom variable C, Pe(c), and draw its CDF Fc(x), accordingly. (d) (15 pts) What is the mean value of C, ie, it-EC]

Answer 1

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