SOLUTION: Can someone please help with the following: determine whether true or false for events A and B. (EXPLAIN ANSWER) P(A U B) - P(B) = P(A) Thnk you sincerely.

Algebra ->  Probability-and-statistics -> SOLUTION: Can someone please help with the following: determine whether true or false for events A and B. (EXPLAIN ANSWER) P(A U B) - P(B) = P(A) Thnk you sincerely.      Log On


   



Question 723696: Can someone please help with the following:
determine whether true or false for events A and B. (EXPLAIN ANSWER)
P(A U B) - P(B) = P(A)
Thnk you sincerely.

Answer by Positive_EV(69) About Me  (Show Source):
You can put this solution on YOUR website!
This is not true for all events A and B. P(A U B) - P(B) = P(A) - P(A ∩ B), in general.
This is a rewritten version of the Inclusion-Exclusion Principle: P(A U B) = P(A) + P(B) - P(A ∩ B).

Your original statement is only true if A and B are mutually exclusive; that is, if only one of A or B (or neither) can ever happen at once.