Question 9 • Financial Math
The equation x + y = 30 means Beau sold 30 books altogether. If all 30 were paperbacks, he would earn $300; the additional $50 came from hardcover books earning $5 more each, so he sold $50 ÷ $5 = 10 hardcovers. That leaves 30 − 10 = 20 paperbacks, so the correct choice is A, 10 hardcovers and 20 paperbacks.
AI-written and checked against the verified answer.