Pawan and Bhanu started a business with their investments in the ratio 5:7. After 6 months, Raju joined the business with an investment of Rs. 3000, and at the same time, Pawan increased his investment by Rs. 900. At the end of one year, the profit was distributed among Pawan, Bhanu, and Raju in the ratio 13:14:10. Find the difference between the initial investments of Pawan and Bhanu.