If each of two independent file servers has a reliability of 93% and either alone can run the website, then the overall website availability is: A)0.8649, B) 0.9300, C) 0.9522, D)0.9951

Question

I came up with B. 0.9300 is this correct

Answer 1

I think D) 0.9951

The probability of failure of machine 1 is 7%. Same for machine 2. The probability they both fail is .07*.07 = .0049 -- Ergo, the prob. that at least one is working is 1-.0049 = .9951