23. A large aircraft manufacturer produces a passenger jet having a navigation component consisting of three sequentially functioning redundant navigation systems that will allow the jet to be properly controlled so long as at least one of the systems remains operational.

The operating life of each of the systems is the outcome of a random variable having the exponential PDF fIx) = .le-·1x IIO,oo)(X), where x is measured in thousands of hours, and the operating lives are independent of one another.

Problems