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2x2xKit

Probability Calculator

Calculate the probability of two independent events happening together, either, or neither.

How this is calculated
P(A and B) = P(A) × P(B). P(A or B) = P(A) + P(B) − P(A and B), for independent events.

Assumptions used in this calculation

  • Independence: Assumes events A and B are independent, the outcome of one doesn't affect the other.

About this calculator

Calculates the probability of two independent events A and B occurring together (both), either one (union), or neither, plus the complement of A.

Worked example

Coin heads (1/2) and rolling a 6 (1/6)

Result: P(both) ≈ 8.33%, P(either) ≈ 58.33%

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