To determine the number of different project combinations possible using the Fundamental Counting Principle, we multiply the number of choices for each category of selection.
- Number of topics: There are 15 choices.
- Number of presentation methods: There are 3 choices (written report, oral presentation, or making a game).
Using the Fundamental Counting Principle, we multiply these numbers together:
\[ \text{Total combinations} = \text{Number of topics} \times \text{Number of presentation methods} = 15 \times 3 = 45 \]
Therefore, the total number of different project combinations possible is 45.