A and B started a business with their initial investments of Rs.180 and X respectively. After 2 years from the start of the business, another person C joins them with investment Rs.300 and A and B invested additional amounts in the ratio of 1:5 respectively. If at the end of 5 years C receives (\(\frac{10}{33}\)) of total profit and the ratio of total profit of B to total profit of C is 7:6, what was the additional amount invested by B?