Validity Probability 1D9Cda
1. **Problem Statement:**
Determine whether the given distribution is a valid probability distribution for a discrete random variable $X$ with values $5, 6, 7, 4$ and probabilities $0.22, 0.35, 0.18, 0.35$ respectively.
2. **Formula and Rules:**
A probability distribution for a discrete random variable must satisfy two conditions:
- Each probability $P(X=x)$ must be between 0 and 1 inclusive.
- The sum of all probabilities must equal 1.
3. **Check each probability:**
- $0.22$ is between 0 and 1.
- $0.35$ is between 0 and 1.
- $0.18$ is between 0 and 1.
- $0.35$ is between 0 and 1.
All probabilities satisfy the first condition.
4. **Sum the probabilities:**
$$0.22 + 0.35 + 0.18 + 0.35 = 1.10$$
5. **Interpretation:**
The sum of probabilities is $1.10$, which is greater than 1. This violates the second condition for a valid probability distribution.
6. **Conclusion:**
Since the sum of probabilities is not equal to 1, the given distribution is **not** a valid probability distribution for the discrete random variable $X$.