Consider a machining shop with a single repairer looking after two machines. Each time machine i being repaired, it stays up and running for an exponentially-distributed amount of time with rates of ?1=2 and ?2=4. When machine i fails, it requires an exponentially-distributed amount of repair time with rates ?1=9 and ?2=12. The repairer repairs the machines implementing a first-come-first-serve policy, e.g., if machine 1 fails while machine 2 is being repaired, machine 1 has to wait. Model this shop floor with a continuous-time Markov chain.