`P(A+B) = P(A) + P(B) - P(A, B) `

Enter a value for all fields

"The probability P(E) of an event E is a real number in the range of 0 to 1. The probability of an impossible event is 0 and that of an event certain to occur is 1."

The Law of Total Probability states that  P(A + B) is the probability that either A or B occur alone or that both occur together.

P(A + B) can be computed from: P(A + B) = P(A) + P(B) – P(A, B), where

• P(A) = the probability that A occurs,
• P(B) = the probability that B occurs, and
• P(A, B) = the probability that both A and B occur simultaneously.

See Also

• Try the Mean calculation
• Try the Median calculation
• Try the Mode calculation
• Here's the Range of a data set
• Here's the Min calculation
• And the Max calculation
• Standard Deviation (Sample)
• Standard Deviation (Population)
• Frequency Distribution between min and max
• Frequency Distribution for population
• Try the z-score calculation on your data set
• Try the z-score when you know both mean and SD
• Law of Total Probability
• Conditional Probability of B given A
• Probability of Equally Likely Events