Instructions: DO NOT USE CALCULATOR. Figures are not drawn to scale. Arif contributed \(\frac{2}{3}\) of his salary to a charity, which is half the salary of Babu. Babu contributed \(\frac{3}{4}\) of his salary to the same charity, which is twice the salary of Malek. Malek contributed \(\frac{1}{4}\) of his salary to the charity. If Babu's salary is Tk. 20,000, what was the total contribution to the charity?

Explanation: (A) Babu's Salary (\(S_B\)) = Tk. 20,000. Arif's Contribution (\(C_A\)): Half of Babu's salary = \(\frac{1}{2} \cdot 20,000 = 10,000\). Arif's Contribution is also \(\frac{2}{3}\) of Arif's salary (\(S_A\)), so \(10,000 = \frac{2}{3} S_A \implies S_A = 15,000\). Babu's Contribution (\(C_B\)): \(\frac{3}{4}\) of Babu's salary = \(\frac{3}{4} \cdot 20,000 = 15,000\). Babu's Contribution is also twice Malek's salary (\(S_M\)), so \(15,000 = 2 \cdot S_M \implies S_M = 7,500\). Malek's Contribution (\(C_M\)): \(\frac{1}{4}\) of Malek's salary = \(\frac{1}{4} \cdot 7,500 = 1,875\). Total Contribution = \(C_A + C_B + C_M = 10,000 + 15,000 + 1,875 = 26,875\).