Answer:
0.58 = 58% probability she passes both courses
Step-by-step explanation:
We can solve this question treating the probabilities as a Venn set.
I am going to say that:
Event A: She passes the first course.
Event B: She passes the second course.
The probability she passes the first course is 0.67.
This means that [tex]P(A) = 0.67[/tex]
The probability she passes the second course is 0.7.
This means that [tex]P(B) = 0.7[/tex]
The probability she passes at least one of the courses is 0.79.
This means that [tex]P(A \cup B) = 0.79[/tex]
a. What is the probability she passes both courses
This is [tex]P(A \cap B)[/tex].
We use the following relation:
[tex]P(A \cup B) = P(A) + P(B) - P(A \cap B)[/tex]
So
[tex]P(A \cap B) = P(A) + P(B) - P(A \cup B) = 0.67 + 0.7 - 0.79 = 0.58[/tex]
0.58 = 58% probability she passes both courses