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Probability of Atleast One Event Occurring given Probability of Events Calculator

Probability of Atleast One Event Occurring Formula:

\[ P(A \cup B \cup C) = P(A) + P(B) + P(C) - (P(A) \times P(B)) - (P(B) \times P(C)) - (P(C) \times P(A)) + (P(A) \times P(B) \times P(C)) \]

(0 to 1)
(0 to 1)
(0 to 1)

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1. What is the Probability of Atleast One Event Occurring?

The probability of at least one event occurring calculates the likelihood that any one or more of the specified events will happen. This is based on the inclusion-exclusion principle in probability theory.

2. How Does the Calculator Work?

The calculator uses the inclusion-exclusion formula:

\[ P(A \cup B \cup C) = P(A) + P(B) + P(C) - (P(A) \times P(B)) - (P(B) \times P(C)) - (P(C) \times P(A)) + (P(A) \times P(B) \times P(C)) \]

Where:

Explanation: The formula accounts for overlapping probabilities by subtracting the intersections and adding back the triple intersection to avoid double-counting.

3. Importance of Probability Calculation

Details: Calculating the probability of at least one event occurring is crucial in risk assessment, decision making, and statistical analysis across various fields including finance, engineering, and scientific research.

4. Using the Calculator

Tips: Enter probabilities for events A, B, and C as values between 0 and 1. All probabilities must be valid (0 ≤ probability ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: What does this probability represent?
A: It represents the likelihood that at least one of the three events (A, B, or C) will occur.

Q2: Are the events assumed to be independent?
A: Yes, this formula assumes that events A, B, and C are independent of each other.

Q3: What if I have only two events?
A: For two events, the formula simplifies to: P(A∪B) = P(A) + P(B) - (P(A) × P(B))

Q4: Can probabilities be greater than 1?
A: No, probabilities must be between 0 and 1. The result will also be between 0 and 1.

Q5: What if events are not independent?
A: This calculator assumes independence. For dependent events, more complex formulas involving conditional probabilities are needed.

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