# Question: In Reliability Ques March 2004 the exponential distribution was used

In Reliability Ques (March 2004), the exponential distribution was used to model the lengths of life of CD-ROM drives in a two-drive system. The two CD-ROM drives operate independently, and at least one drive must be operating for the system to operate successfully. Both drives have a mean length of life of 25,000 hours.

a. The reliability R(t) of a single CD-ROM drive is the probability that the life of the drive exceeds t hours. Give a formula for R(t).

b. Use the result from part a to find the probability that the life of the single CD-ROM drive exceeds 8,760 hours (the number of hours of operation in a year).

c. The reliability S(t) of the two-CD-ROM-drive system is the probability that the life of at least one drive exceeds t hours. Give a formula for S( t ).

d. Use the result from part c to find the probability that the two-drive CD-ROM system has a life whose length exceeds 8,760 hours.

e. Compare the probabilities you found in parts b and d.

a. The reliability R(t) of a single CD-ROM drive is the probability that the life of the drive exceeds t hours. Give a formula for R(t).

b. Use the result from part a to find the probability that the life of the single CD-ROM drive exceeds 8,760 hours (the number of hours of operation in a year).

c. The reliability S(t) of the two-CD-ROM-drive system is the probability that the life of at least one drive exceeds t hours. Give a formula for S( t ).

d. Use the result from part c to find the probability that the two-drive CD-ROM system has a life whose length exceeds 8,760 hours.

e. Compare the probabilities you found in parts b and d.

**View Solution:**## Answer to relevant Questions

An essential tool in the monitoring of the quality of a manufactured product is acceptance sampling. An acceptance sampling plan involves knowing the distribution of the life length of the item produced and determining how ...Assume that x has an exponential distribution with θ = 3. Find a. P(x ≤ 1) b. P(x > 1) c. P(x = 1) d. P(x ≤ 6) e. P(2 ≤ x ≤ 10) Refer to the Teaching Psychology (May 1998) study of how external clues influence performance, presented in Exercise. Recall that two different forms of a midterm psychology examination were given, one printed on blue paper ...An article in IEEE Transactions (Mar. 1990) gave an example of a flexible manufacturing system with four machines operating independently. The repair rates for the machines (i.e., the time, in hours, it takes to repair a ...Refer to Exercise 6.7, in which we found the sampling distribution of the sample median. Is the median an unbiased estimator of the population mean μ?Post your question