Answer: 0.24
Step-by-step explanation:
Denote [tex]P(A), P(E), P(S)[/tex] as the probabilities that you get an A in Accounting, Economics and Statistics, respectively.
As the performance in each course is independent of that in any other courses, we can apply the addition rule as follows:
[tex]P(new\:car) = P[(A \cap E) \cup S] = P(A \cap E) + P(S)[/tex]
Similarly, under the assumption of independent performance in each course, we can apply the multiplication rule as follows:
[tex]P(A \cap E) = P(A) \times P(E) = 0.2 \times 0.2 = 0.04[/tex]
We also know that [tex]P(S) = 0.2[/tex]
As such, it can be concluded: [tex]P(new\:car) = 0.04 + 0.2 = 0.24[/tex]