'R' and 'S' invested 30000 Rs. and 'x' Rs. respectively to start a startup together. At the end of every year, 'R' got a fixed amount as an annual salary from the annual profit. After 'R' was paid his salary, the remaining profit was distributed to both of them in the ratio of their investments. If at the end of the first year, the total amounts received by 'R' and 'S' were in the ratio of 5 : 3 respectively, and 'R' received 40% of the total profit as his salary then find the value of 'x'?