1. **State the problem:** We need to find which probability distribution table has a mean (expected value) of $7$ for the random variable $X$ representing profit.
2. **Recall the formula for the mean of a discrete probability distribution:**
$$\mu = E(X) = \sum (x \cdot P(x))$$
where $x$ are the values of the random variable and $P(x)$ are their probabilities.
3. **Check each table by calculating the mean:**
- Top-left table:
$$5 \times 0.4 + 8 \times 0.5 + 10 \times 0.1 = 2 + 4 + 1 = 7$$
- Top-right table:
$$5 \times 0.2 + 8 \times 0.7 + 10 \times 0.1 = 1 + 5.6 + 1 = 7.6$$
- Bottom-left table:
$$5 \times 0.3 + 8 \times 0.5 + 10 \times 0.2 = 1.5 + 4 + 2 = 7.5$$
- Bottom-right table:
$$5 \times 0.6 + 8 \times 0.1 + 10 \times 0.3 = 3 + 0.8 + 3 = 6.8$$
4. **Interpretation:** Only the top-left table has a mean of exactly $7$.
**Final answer:** The top-left table represents the probability distribution for $X$ with mean $7$.
Mean Probability 56Ffb6
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