1. **State the problem:** A fair coin is flipped. If a head turns up, you win 3. If a tail turns up, you lose 3. We want to find the expected value of the game and determine if the game is fair.
2. **Formula for expected value:** The expected value $E$ of a discrete random variable is given by
$$E = \sum (\text{outcome} \times \text{probability of outcome})$$
3. **Identify outcomes and probabilities:**
- Winning 3 with probability $\frac{1}{2}$ (head)
- Losing 3 with probability $\frac{1}{2}$ (tail)
4. **Calculate expected value:**
$$E = 3 \times \frac{1}{2} + (-3) \times \frac{1}{2}$$
5. **Simplify:**
$$E = \frac{3}{2} - \frac{3}{2}$$
$$E = \cancel{\frac{3}{2}} - \cancel{\frac{3}{2}} = 0$$
6. **Interpretation:** The expected value is 0, meaning on average, you neither gain nor lose money.
7. **Is the game fair?** A game is fair if the expected value is 0. Since $E=0$, the game is fair.
**Final answer:** The expected value of the game is $0$. So, the game is fair.
Expected Value Coin 53D3E8
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