Suppose that for a cable company the repair time to restore service after an unexpected service interruptions has an exponential probability distribution with mean of 2.5 hours. a. What is the probability that the cable service will be repaired within 30 minutes? b. What is the probability that the repair will take between 45 minutes and an hour and half? c. For a customer who calls the cable company office at 2:00 P.M., what is the probability that the cable service will not be repaired by 4:00 P.M.?
Added by Pamela G.
Step 1
The mean of an exponential distribution is given by 1/λ, so we have: 1/λ = 2.5 hours λ = 1/2.5 = 0.4 per hour Now, we can answer each part of the question: a. We want to find the probability that the repair time is less than 30 minutes (0.5 hours). The Show more…
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