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Module · Math · Statistics
Probability Calculator
Compute union, intersection, complement and conditional probabilities for two events. Toggle between independent and dependent events.
P(A ∪ B) — union76%
P(A ∩ B) — intersection24%
P(A') — complement of A40%
P(B')60%
P(A | B) — cond. of A given B60%
P(B | A)40%
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Guide
How Probability works
Step 01
Enter P(A) and P(B)
Values between 0 and 1.
Step 02
Independent or not?
If independent, P(A∩B) = P(A) × P(B) automatically.
Step 03
See all measures
Union, intersection, complement, both conditionals.
FAQ
Frequently asked
Independent vs dependent?+
Independent events don't influence each other — flipping heads twice. Dependent — drawing cards without replacement.
Bayes' theorem?+
P(A|B) = P(A∩B) / P(B). Shown directly in the results.