Answer: 0.8
Explanation:
Given :
Outcome - - - - A - - - - - B - - - - - C - - - - - D
Probability - - 0.5 - - - 0.3 - - - - - -? - - - - -?
Probability of the outcome (A or B) :
(A or B) is the union of two outcomes, that is union of outcome A with the the outcome of B. Usually interpreted as containing elements of both A and B.
The probability denoted as (A or B) of two different outcomes is the sum of the individual probability of A and probability of B
Therefore,
(A or B) = 0.5 + 0.3 = 0.8