A costs thrice as much as B. A is sold at a loss of 10%, and B is sold at \(\frac{5}{4}\) of its own price. If the selling price of A is Rs. 5,800 more than the selling price of B, then the cost price of A is:
1
Rs. 9,600
2
Rs. 15,000
3
Rs. 12,000
4
Rs. 4,000