P and Q started a business by investing &rupee;8000 and &rupee;4000 respectively. After 4 months, P withdrew &rupee;1000 from his investment. After 4 more months, Q increased his investment by &rupee;x. If the ratio of the profit shares of P to Q at the end of the year is 22:15, then find the value of 3x.

Three partners invested in a business in the ratio 8:5:4. They invested their capital for 3 months, 10 months, and 9 months respectively. What was the ratio of their profits?

A started a business with an investment of ₹21,000 and after a few months, B joined him with an investment of ₹15,000. At the end of the year, the total profit was divided between them in the ratio 12 : 5. After how many months did B join the business?