Answer:
45 quarters
Step-by-step explanation:
1. Think of this as the ration equation 9/3=x/15 where x is the number of quarters to play 15 levels
2. To solve the ratio, you need to cross multiply, and then divide
3. Multiply 9 times 15 (135)
4. Divide that number by 3 (45), and that's your answer!