Rohit borrowed Rs. 15,000 from his friend at compound interest of 20% p.a., compounding annually. He added Rs. 'X' to this money and lent the total sum to Suresh at simple interest of 10% p.a. for 2 years. If total profit earned by Rohit at the end of 2 years is Rs. 1,200, then find the value of 'X'.