Probability Calculator
Combine the probabilities of two events: both, either, neither, exactly one, and not A.
P(A and B)
0.2 (20%)
- P(A or B)
- 0.7 (70%)
- P(exactly one)
- 0.5 (50%)
- P(neither)
- 0.3 (30%)
- P(not A)
- 0.5 (50%)
- P(not B)
- 0.6 (60%)
Show the work
Independent: multiply
P(A and B) = P(A) × P(B)
50% × 40% = 0.2 (20%)
How it works
Independent: P(A and B) = P(A) × P(B); mutually exclusive: P(A and B) = 0; P(A or B) = P(A) + P(B) − P(A and B); P(not A) = 1 − P(A)
Questions
- How does the probability calculator work?
- Independent: P(A and B) = P(A) × P(B); mutually exclusive: P(A and B) = 0; P(A or B) = P(A) + P(B) − P(A and B); P(not A) = 1 − P(A).
- What do I need to enter?
- P(A), P(B), The events are. Optional fields can be left blank.
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