What is sum of the probablities of all the possible events of a random experiment ?

Answer

To find the sum of the probabilities of all possible events of a random experiment, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Probability**:
- Probability measures the likelihood of an event occurring and is always a value between 0 and 1.

2. **Identify Possible Events**:
- In a random experiment, let’s denote the possible events as \( E_1, E_2, E_3, \ldots, E_n \).

3. **Assign Probabilities**:
- Each event \( E_i \) has an associated probability \( p_i \) where \( i \) ranges from 1 to \( n \). Thus, we have probabilities \( p_1, p_2, p_3, \ldots, p_n \).

4. **Sum of Probabilities**:
- According to the fundamental principle of probability, the sum of the probabilities of all possible events must equal 1. This can be expressed mathematically as:
\[ p_1 + p_2 + p_3 + \ldots + p_n = 1 \]

5. **Conclusion**:
- Therefore, the sum of the probabilities of all possible events in a random experiment is always equal to 1.

### Final Answer:
The sum of the probabilities of all the possible events of a random experiment is **1**.

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