A professor finds that she awards a final grade of A to 20% of her students. Of

Question:

A professor finds that she awards a final grade of A to 20% of her students. Of those who obtain a final grade of A, 70% obtained an A on the midterm examination.
Also, 10% of the students who failed to obtain a final grade of A earned an A on the midterm exam. What is the probability that a student with an A on the midterm examination will obtain a final grade of A?