Exercise 2 Page 843

When calculating the experimental probability, we are comparing the $\text{number}$ $\text{of}$ $\text{times}$ $\text{the}$ $\text{event}$ $\text{occurs}$ to the $\text{number}$ $\text{of}$ $\text{times}$ $\text{the}$ $\text{experiment}$ $\text{is}$ $\text{done}.$ This is very similar to the Probability Formula. We are told that a total of $8$ red, $10$ blue, $9$ green, and $12$ yellow colored tiles were randomly selected. The sum of these values is the $\text{number}$ $\text{of}$ $\text{times}$ $\text{the}$ $\text{experiment}$ $\text{is}$ $\text{done}.$ Out of these, $9$ are green, which is the $\text{number}$ $\text{of}$ $\text{times}$ $\text{the}$ $\text{event}$ $\text{occurs}.$ Now we have enough information to calculate $P(\text{green}).$ The experimental probability of choosing a green tile is $\frac{3}{13}.$