Question

A tank contains 70 kg of salt and 1000 L of water. Pure water enters a tank at the rate 6 L/min. The solution is mixed and drains from the tank at the rate 3 L/min. What is the amount of salt in the tank initially?

Answer 1

The initial amount of salt in the tank is 70 kg, which does not change due to the flows of water since the question only asks about the initial state.

Step-by-step explanation:

The student has asked about the initial amount of salt in a tank which contains a mixture of salt and water. Initially, the tank contains 70 kg of salt and 1000 L of water. Despite the flows of pure water entering and draining from the tank, the initial mass of salt remains the same at 70 kg. This problem is a typical example of a calculation involving concentrations and mixtures, often seen in Chemistry.