A certain sum of money is to be divided among a certain number of men; if there were 3 men fewer, each man would have Rs. 150 more but if there were 6 men more each man would have Rs. 120 less. Find the sum of money and the number of men.

You have three equations in three unknowns (number of men, total amount of money, and amount received by each). Show us how you set these equations up and then try to solve - we'll help if you get stuck, but you must show us your attempt.