In a particular year the average monthly expenditure of Vipin was ₹ 6,250 during the first 4 months, ₹ 6,500 during the next 4 months, and ₹x during the remaining months of the year. If the total savings in the year was ₹ 15,000 and his monthly salary is ₹ 9,600, then find the value of x.