Mathematics · Time and Work

Four pipes A, B, C, and D are connected to a tank. Pipe A and Pipe B are inlet pipes, while the others are outlet pipes. The efficiency of Pipe A is 25% less than the efficiency of Pipe B. Pipe A takes [t + 10] hours to fill the tank alone, and Pipe B alone fills the tank in [t + 5] hours. Pipes C and D can empty the tank alone in [d + 4] and [d + 10] hours respectively. Pipes A and D together can fill the tank in [t + 50] hours. When all four pipes are opened together, the tank is filled in 5 hours. The efficiency of pipe C is 25% more than that of pipe D. Quantity I: Value of d Quantity II: Value of t