Answer:
See below
Explanation:
He misinterpreted P(A|B) as P(A∩B) and calculated that instead. P(A|B)=0.17 represents the probability that the student takes Chemistry given they've taken Algebra 2, while P(A∩B) represents the probability that the student takes both Chemistry and Algebra 2. Here's how the problem should've been done:

Therefore, the correct probability that the student will take both Chemistry and Algebra 2 is 0.136, or 13.6%