We will write an equation for the total number of possible outcomes P when a multistage experiment is performed with k stages. We are given that a multistage experiment has n possible outcomes at each stage, so from the first stage to the k^\text{th} stage each stage has n possible outcomes.
Stage
Number of Possible Outcomes
1^\text{st} Stage
n
2^\text{nd} Stage
n
3^\text{rd} Stage
n
...
...
k^\text{th} Stage
n
With this information to write the equation, we can use the Fundamental Counting Principle. Since there are k stages we will multiple n by itself k times.
