# Question

A TV system is expected to last for 50,000 hours before failure. Assume an exponential distribution for the time until failure.

a. Is the distribution skewed or symmetric?

b. What is the standard deviation of the length of time until failure?

c. The system has been working continuously for the past 8,500 hours and is still on. What is the expected time from now until failure? (Be careful!)

a. Is the distribution skewed or symmetric?

b. What is the standard deviation of the length of time until failure?

c. The system has been working continuously for the past 8,500 hours and is still on. What is the expected time from now until failure? (Be careful!)

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