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This has to do with the union of events. If events A and B are in the set S, then the union of A and B is the set of outcomes in A or B. This means that either event A or event B, or both, can occur.
P(A or B) = P(A) + P(B) - P(A and B)
**P(A and B) is subtracted, since by taking P(A) + P(B), their intersection, P(A and B), has already been included. In other words, if you did not subtract it, you would be including their intersection twice. Draw a Venn Diagram to visualize.
If A and B can only happen separately, i.e., they are independent events and thus P(A and B) = 0, then,
P(A or B) = P(A) + P(B) - P(A and B) = P(A) + P(B) - 0 = P(A) + P(B)
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science
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http://www.emathzone.com/tutorials/basic-statistics/definition-of-probability.html
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Since probability is not a geometric concept, there is no definition for it in geometry.
When the number is added to its additive inverse what is the sum equal to?
It is zero, by definition of additive inverse!
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False; the "or" is an additive property so the probability of rain or snow muse be greater than or equal to 0.65.
What is the definition of sure or certain events in probability?
If an event is certain, the probability is 1.
What is the definition for probability sample?
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What is the definition of additive inverses?
A pair of numbers whose sum is zero. The additive inverse of 10 is -10 because 10+(-10) = 0.
What is the definition of probability in composite risk management?
science
What is mathematical definition of random process?
Probability model
The word that goes to this definition a probability of 0 means the event is?
A probability of 0 means the event is impossible.
What is the probability of Saturday following Friday?
The probability is 1:1 (1 in 1) or 100% (by calendar definition).
