TATITIC CALCULATOR
Or Probability
A precise tool.
What is the Or Probability & How does it work?
The union of two events A and B represents the occurrence of either event or both.
In probability theory, the additive rule adjusts for double‑counting the overlap by subtracting the intersection.
This calculator applies the formula to give the combined probability, ensuring the result stays within the [0,1] interval.
P(A cup B) = P(A) + P(B) – P(A cap B)
P(A) = probability of event A, P(B) = probability of event B, P(A cap B) = probability of both A and B occurring
Parameters
Result
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Frequently Asked Questions
How do I use the Or Probability Calculator?
Enter the probabilities of events A and B, along with their intersection, into the calculator to find P(A ∪ B).
What does P(A ∩ B) represent in this calculator?
P(A ∩ B) represents the probability that both event A and event B occur.
Can I use this calculator for more than two events?
This calculator is specifically designed for two events. For more, consider using a different tool or manually applying the formula.
Why do we subtract P(A ∩ B) in the formula?
Subtracting P(A ∩ B) prevents double-counting the probability of both A and B occurring when adding P(A) and P(B).
What is the range of values this calculator will return?
The calculator ensures the result stays within the [0,1] interval, representing a valid probability.
How does this calculator handle mutually exclusive events?
For mutually exclusive events, P(A ∩ B) = 0. The formula simplifies to P(A ∪ B) = P(A) + P(B).
Is there a limit to the probability values I can input?
Yes, you should input probabilities between 0 and 1, inclusive.
Results are for informational purposes only and do not constitute professional advice.