Radha invested her savings in schemes A and B in the ratio 5 ∶ 9, each for \(1\frac{1}{2}\) years. Scheme A offers interest at 20% p.a. compounded half yearly, and scheme B offers interest at the same rate, compounded yearly. If the total interest received from both the schemes after \(1\frac{1}{2}\) years is Rs. 13,605, the sum invested by her in scheme A is: