P
Probability Calculator
The chances of both, either, or neither of two independent events happening.
Result…
How it's calculated
P(A and B) = P(A) × P(B) P(A or B) = P(A) + P(B) − P(A) × P(B) P(neither) = (1 − P(A)) × (1 − P(B))
These rules hold for independent events, such as two coin tosses or two separate dice. When events depend on each other (drawing cards without putting them back), P(A and B) = P(A) × P(B given A) instead.
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