# 11.4.1. Calculating Probability

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.

- A0.13
- B0.84
- C0.03
- D0.71

### Example

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.

### Solution

In this case, event

Thus, the probability of the student's success in only mathematics is 0.13.