Exercise Three 1) According to the reliability rating, how many units on average would you expect to fail in one week? Reliability of 168 hours = e^((Ln .97 = e^(-failure rate*17520))*168)=.999708; thus, probability of failure is 1-.99708 = .000292032 or (.000292032 Probability of failure) X (1000 units/week production) = .292032 units failing each week 2) From the 30 weeks of data supplied, on average, what is the proportion failing?