Economics and Finance
A taxpayer in need of advice will call the IRS repeatedly until she can get through (no busy signal). If she receives a busy signal, she will hang up and try again later, and will stop calling as soon as she reaches an agent.
An experiment consists of recording the calling pattern. A possible outcome is BBH: a busy signal (B) on the first two calls, and (finally) help (H) on the third call.
a. How many possible outcomes are there in this experiment?
b. List some of the outcomes for this experiment.