If the success probability of a student in physics is 0.71, in mathematics is 0.81, and in both subjects is 0.68, find his success probability in mathematics ONLY.
In this case, event is the student's success in physics, and event is the student's success in mathematics.
The notation refers to the probability of the occurrence of and the non-occurrence of .
Also, the notation refers to the probability of events and occurring together.
For this reason, is equal to the sum of and . Find as follows:
Thus, the probability of the student's success in only mathematics is 0.13.