IBPS RRB Office Assistant Mains 24 Sep 2022 Paper

A started a business investing Rs. 3000. After 3 months, B joined the business investing Rs. 2000. After some more time, C joined the business investing Rs. 1500. At the end of the year, profit from the business was Rs. 16000 and share of C was Rs.1600 out of the profit. For how many months C invested in the business?