1. Problem: Calculate the theoretical probability of getting an odd number when rolling a fair dice. 2. Formula: The theoretical probability of an event is given by $$P(e) = \frac{\text{Number of favorable outcomes}}{\text{Total number of possible outcomes}}$$ 3. All possible outcomes when rolling a fair dice are the numbers 1 through 6: $$\{1, 2, 3, 4, 5, 6\}$$ 4. Favorable outcomes for getting an odd number are: $$\{1, 3, 5\}$$ 5. Number of favorable outcomes = 3 6. Total number of possible outcomes = 6 7. Calculate the probability: $$P(e) = \frac{3}{6} = \frac{1}{2}$$ 8. Explanation: Since there are 3 odd numbers out of 6 possible outcomes, the probability of rolling an odd number is one half. Final answer: $$P(e) = \frac{1}{2}$$