A system contains two components, A and B. Both components must function for the system to work. The probability that component A fails is 0.08, and the probability that component B fails is 0.05. Assume the two component function independently. What is the probability that the syetem function?
Solution
The probability that the system function is the probability that both components function. Therefore
P(system function) = P(A functions and B functions)
Since the components function independently,
P(A functions and B functions) = P(A functions) P(B functions)
= [1- P(A fails)][ 1- P(B fails)]
= (1-0.08)(1-0.05)
= 0.874