The table summarizes the distribution of color and shape for 100 tiles of equal area.
| Shape | Red | Blue | Yellow | Total |
|---|---|---|---|---|
| Square | 10 | 20 | 25 | 55 |
| Pentagon | 20 | 10 | 15 | 45 |
| Total | 30 | 30 | 40 | 100 |
If one of these tiles is selected at random, what is the probability of selecting a red tile?
Enter a number or fraction, e.g. 5, 0.5, 1/2
Explanation
The correct answer is . It's given that there are a total of tiles of equal area, which is the total number of possible outcomes. According to the table, there are a total of red tiles. The probability of an event occurring is the ratio of the number of favorable outcomes to the total number of possible outcomes. By definition, the probability of selecting a red tile is given by , or . Note that and are examples of ways to enter a correct answer.