Online Probability Calculator
Calculate probability of single, multiple, and conditional events. Determine odds for series of trials, independent coin tosses, and dice rolls.
How to use
- Input number of favorable outcomes m and total possible outcomes n.
- For compound events, enter individual probabilities P(A) and P(B).
- Select event relationship (mutually exclusive, independent, union).
- View computed odds in decimals and percentage format.
Classical Probability Rules
Single event probability: P(A) = m / n (favorable outcomes / total sample space).
Independent events intersection: P(A and B) = P(A) * P(B).
Union of events (either occurs): P(A or B) = P(A) + P(B) - P(A and B).
Complementary event: P(not A) = 1 - P(A).
Calculation Methodology
Probability values strictly span [0, 1] (or 0% to 100%), adhering to Kolmogorov probability axioms.
Frequently Asked Questions
What is probability?
The mathematical likelihood of an event occurring, quantified as a value from 0 to 1.
How do you find the complement of an event?
Subtract the event probability from 1: P(A') = 1 - P(A).
What makes events independent?
Events are independent when the occurrence of one does not affect the probability of the other.
Can probability exceed 1 or 100%?
No, the upper limit for absolute certainty is exactly 1 (100%).
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