Q. Ravi starts a business with $ 45000. After a certain period of time he is joined by Mohan who invests $ 30000. At the end of the year they divide the profit in the ratio 9 : 4. When did Mohan join Ravi?

• A. After 3 months
• B. After 5 months
• C. After 6 months
• D. After 4 months

Correct Answer: D